merge

73 files changed, 5245 insertions, 633 deletions

diff --git a/indra/llcommon/CMakeLists.txt b/indra/llcommon/CMakeLists.txt
index 907dbab8f8..16b42dad38 100644
--- a/indra/llcommon/CMakeLists.txt
+++ b/indra/llcommon/CMakeLists.txt
@@ -10,7 +10,6 @@ include(Boost)
 include(LLSharedLibs)
 include(JsonCpp)
 include(GoogleBreakpad)
-include(GooglePerfTools)
 include(Copy3rdPartyLibs)
 include(ZLIB)
 include(URIPARSER)
@@ -40,8 +39,11 @@ set(llcommon_SOURCE_FILES
     llbase64.cpp
     llbitpack.cpp
     llcallbacklist.cpp
+    llcallstack.cpp
+    llcleanup.cpp
     llcommon.cpp
     llcommonutils.cpp
+    llcoro_get_id.cpp
     llcoros.cpp
     llcrc.cpp
     llcriticaldamp.cpp
@@ -58,6 +60,7 @@ set(llcommon_SOURCE_FILES
     lleventfilter.cpp
     llevents.cpp
     lleventtimer.cpp
+    llexception.cpp
     llfasttimer.cpp
     llfile.cpp
     llfindlocale.cpp
@@ -65,7 +68,9 @@ set(llcommon_SOURCE_FILES
     llformat.cpp
     llframetimer.cpp
     llheartbeat.cpp
+    llheteromap.cpp
     llinitparam.cpp
+    llinitdestroyclass.cpp
     llinstancetracker.cpp
     llleap.cpp
     llleaplistener.cpp
@@ -114,6 +119,7 @@ set(llcommon_SOURCE_FILES
     llworkerthread.cpp
     timing.cpp
     u64.cpp
+    StackWalker.cpp
     )
     
 set(llcommon_HEADER_FILES
@@ -134,8 +140,11 @@ set(llcommon_HEADER_FILES
     llbitpack.h
     llboost.h
     llcallbacklist.h
+    llcallstack.h
+    llcleanup.h
     llcommon.h
     llcommonutils.h
+    llcoro_get_id.h
     llcoros.h
     llcrc.h
     llcriticaldamp.h
@@ -157,6 +166,7 @@ set(llcommon_HEADER_FILES
     lleventfilter.h
     llevents.h
     lleventemitter.h
+    llexception.h
     llfasttimer.h
     llfile.h
     llfindlocale.h
@@ -166,7 +176,9 @@ set(llcommon_HEADER_FILES
     llhandle.h
     llhash.h
     llheartbeat.h
+    llheteromap.h
     llindexedvector.h
+    llinitdestroyclass.h
     llinitparam.h
     llinstancetracker.h
     llkeythrottle.h
@@ -183,6 +195,7 @@ set(llcommon_HEADER_FILES
     llmortician.h
     llnametable.h
     llpointer.h
+    llpounceable.h
     llpredicate.h
     llpreprocessor.h
     llpriqueuemap.h
@@ -235,6 +248,7 @@ set(llcommon_HEADER_FILES
     stringize.h
     timer.h
     u64.h
+    StackWalker.h
     )
 
 set_source_files_properties(${llcommon_HEADER_FILES}
@@ -244,13 +258,13 @@ list(APPEND llcommon_SOURCE_FILES ${llcommon_HEADER_FILES})
 
 if(LLCOMMON_LINK_SHARED)
   add_library (llcommon SHARED ${llcommon_SOURCE_FILES})
-  if(NOT WORD_SIZE EQUAL 32)
+  if(NOT ADDRESS_SIZE EQUAL 32)
     if(WINDOWS)
-      add_definitions(/FIXED:NO)
+      ##add_definitions(/FIXED:NO)
     else(WINDOWS) # not windows therefore gcc LINUX and DARWIN
       add_definitions(-fPIC)
     endif(WINDOWS)
-  endif(NOT WORD_SIZE EQUAL 32)
+  endif(NOT ADDRESS_SIZE EQUAL 32)
   if(WINDOWS)
     # always generate llcommon.pdb, even for "Release" builds
     set_target_properties(llcommon PROPERTIES LINK_FLAGS "/DEBUG")
@@ -315,7 +329,7 @@ if (LL_TESTS)
   LL_ADD_INTEGRATION_TEST(llprocinfo "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llrand "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llsdserialize "" "${test_libs}")
-  LL_ADD_INTEGRATION_TEST(llsingleton "" "${test_libs}")                          
+  LL_ADD_INTEGRATION_TEST(llsingleton "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llstring "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(lltrace "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(lltreeiterators "" "${test_libs}")
@@ -327,9 +341,12 @@ if (LL_TESTS)
   LL_ADD_INTEGRATION_TEST(llprocess "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llleap "" "${test_libs}")
   LL_ADD_INTEGRATION_TEST(llstreamqueue "" "${test_libs}")
+  LL_ADD_INTEGRATION_TEST(llpounceable "" "${test_libs}")
+  LL_ADD_INTEGRATION_TEST(llheteromap "" "${test_libs}")
+
+## llexception_test.cpp isn't a regression test, and doesn't need to be run
+## every build. It's to help a developer make implementation choices about
+## throwing and catching exceptions.
+##LL_ADD_INTEGRATION_TEST(llexception "" "${test_libs}")
 
-  # *TODO - reenable these once tcmalloc libs no longer break the build.
-  #ADD_BUILD_TEST(llallocator llcommon)
-  #ADD_BUILD_TEST(llallocator_heap_profile llcommon)
-  #ADD_BUILD_TEST(llmemtype llcommon)
 endif (LL_TESTS)
diff --git a/indra/llcommon/StackWalker.cpp b/indra/llcommon/StackWalker.cpp
new file mode 100644
index 0000000000..c0d3104099
--- /dev/null
+++ b/indra/llcommon/StackWalker.cpp
@@ -0,0 +1,1388 @@
+/**********************************************************************
+ * 
+ * StackWalker.cpp
+ * http://stackwalker.codeplex.com/
+ *
+ *
+ * $LicenseInfo:firstyear=2016&license=bsd$
+ *
+ * Linden notes: Small modifications from the original source at https://stackwalker.codeplex.com/
+ *
+ * History:
+ *  2005-07-27   v1    - First public release on http://www.codeproject.com/
+ *                       http://www.codeproject.com/threads/StackWalker.asp
+ *  2005-07-28   v2    - Changed the params of the constructor and ShowCallstack
+ *                       (to simplify the usage)
+ *  2005-08-01   v3    - Changed to use 'CONTEXT_FULL' instead of CONTEXT_ALL 
+ *                       (should also be enough)
+ *                     - Changed to compile correctly with the PSDK of VC7.0
+ *                       (GetFileVersionInfoSizeA and GetFileVersionInfoA is wrongly defined:
+ *                        it uses LPSTR instead of LPCSTR as first paremeter)
+ *                     - Added declarations to support VC5/6 without using 'dbghelp.h'
+ *                     - Added a 'pUserData' member to the ShowCallstack function and the 
+ *                       PReadProcessMemoryRoutine declaration (to pass some user-defined data, 
+ *                       which can be used in the readMemoryFunction-callback)
+ *  2005-08-02   v4    - OnSymInit now also outputs the OS-Version by default
+ *                     - Added example for doing an exception-callstack-walking in main.cpp
+ *                       (thanks to owillebo: http://www.codeproject.com/script/profile/whos_who.asp?id=536268)
+ *  2005-08-05   v5    - Removed most Lint (http://www.gimpel.com/) errors... thanks to Okko Willeboordse!
+ *  2008-08-04   v6    - Fixed Bug: Missing LEAK-end-tag
+ *                       http://www.codeproject.com/KB/applications/leakfinder.aspx?msg=2502890#xx2502890xx
+ *                       Fixed Bug: Compiled with "WIN32_LEAN_AND_MEAN"
+ *                       http://www.codeproject.com/KB/applications/leakfinder.aspx?msg=1824718#xx1824718xx
+ *                       Fixed Bug: Compiling with "/Wall"
+ *                       http://www.codeproject.com/KB/threads/StackWalker.aspx?msg=2638243#xx2638243xx
+ *                       Fixed Bug: Now checking SymUseSymSrv
+ *                       http://www.codeproject.com/KB/threads/StackWalker.aspx?msg=1388979#xx1388979xx
+ *                       Fixed Bug: Support for recursive function calls
+ *                       http://www.codeproject.com/KB/threads/StackWalker.aspx?msg=1434538#xx1434538xx
+ *                       Fixed Bug: Missing FreeLibrary call in "GetModuleListTH32"
+ *                       http://www.codeproject.com/KB/threads/StackWalker.aspx?msg=1326923#xx1326923xx
+ *                       Fixed Bug: SymDia is number 7, not 9!
+ *  2008-09-11   v7      For some (undocumented) reason, dbhelp.h is needing a packing of 8!
+ *                       Thanks to Teajay which reported the bug...
+ *                       http://www.codeproject.com/KB/applications/leakfinder.aspx?msg=2718933#xx2718933xx
+ *  2008-11-27   v8      Debugging Tools for Windows are now stored in a different directory
+ *                       Thanks to Luiz Salamon which reported this "bug"...
+ *                       http://www.codeproject.com/KB/threads/StackWalker.aspx?msg=2822736#xx2822736xx
+ *  2009-04-10   v9      License slihtly corrected (<ORGANIZATION> replaced)
+ *  2009-11-01   v10     Moved to http://stackwalker.codeplex.com/
+ *  2009-11-02   v11     Now try to use IMAGEHLP_MODULE64_V3 if available
+ *  2010-04-15   v12     Added support for VS2010 RTM
+ *  2010-05-25   v13     Now using secure MyStrcCpy. Thanks to luke.simon:
+ *                       http://www.codeproject.com/KB/applications/leakfinder.aspx?msg=3477467#xx3477467xx
+ *  2013-01-07   v14     Runtime Check Error VS2010 Debug Builds fixed:
+ *                       http://stackwalker.codeplex.com/workitem/10511
+ *
+ *
+ * LICENSE (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ *   Copyright (c) 2005-2013, Jochen Kalmbach
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without modification, 
+ *   are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, 
+ *   this list of conditions and the following disclaimer. 
+ *   Redistributions in binary form must reproduce the above copyright notice, 
+ *   this list of conditions and the following disclaimer in the documentation 
+ *   and/or other materials provided with the distribution. 
+ *   Neither the name of Jochen Kalmbach nor the names of its contributors may be 
+ *   used to endorse or promote products derived from this software without 
+ *   specific prior written permission. 
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ *   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
+ *   THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ *   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
+ *   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
+ *   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+ *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 
+ *   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
+ *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ **********************************************************************/
+#if LL_WINDOWS
+
+#include <windows.h>
+#include <tchar.h>
+#include <stdio.h>
+#include <stdlib.h>
+#pragma comment(lib, "version.lib")  // for "VerQueryValue"
+#pragma warning(disable:4826)
+
+#include "StackWalker.h"
+
+
+// If VC7 and later, then use the shipped 'dbghelp.h'-file
+#pragma pack(push,8)
+#if _MSC_VER >= 1300
+#include <dbghelp.h>
+#else
+// inline the important dbghelp.h-declarations...
+typedef enum {
+    SymNone = 0,
+    SymCoff,
+    SymCv,
+    SymPdb,
+    SymExport,
+    SymDeferred,
+    SymSym,
+    SymDia,
+    SymVirtual,
+    NumSymTypes
+} SYM_TYPE;
+typedef struct _IMAGEHLP_LINE64 {
+    DWORD                       SizeOfStruct;           // set to sizeof(IMAGEHLP_LINE64)
+    PVOID                       Key;                    // internal
+    DWORD                       LineNumber;             // line number in file
+    PCHAR                       FileName;               // full filename
+    DWORD64                     Address;                // first instruction of line
+} IMAGEHLP_LINE64, *PIMAGEHLP_LINE64;
+typedef struct _IMAGEHLP_MODULE64 {
+    DWORD                       SizeOfStruct;           // set to sizeof(IMAGEHLP_MODULE64)
+    DWORD64                     BaseOfImage;            // base load address of module
+    DWORD                       ImageSize;              // virtual size of the loaded module
+    DWORD                       TimeDateStamp;          // date/time stamp from pe header
+    DWORD                       CheckSum;               // checksum from the pe header
+    DWORD                       NumSyms;                // number of symbols in the symbol table
+    SYM_TYPE                    SymType;                // type of symbols loaded
+    CHAR                        ModuleName[32];         // module name
+    CHAR                        ImageName[256];         // image name
+    CHAR                        LoadedImageName[256];   // symbol file name
+} IMAGEHLP_MODULE64, *PIMAGEHLP_MODULE64;
+typedef struct _IMAGEHLP_SYMBOL64 {
+    DWORD                       SizeOfStruct;           // set to sizeof(IMAGEHLP_SYMBOL64)
+    DWORD64                     Address;                // virtual address including dll base address
+    DWORD                       Size;                   // estimated size of symbol, can be zero
+    DWORD                       Flags;                  // info about the symbols, see the SYMF defines
+    DWORD                       MaxNameLength;          // maximum size of symbol name in 'Name'
+    CHAR                        Name[1];                // symbol name (null terminated string)
+} IMAGEHLP_SYMBOL64, *PIMAGEHLP_SYMBOL64;
+typedef enum {
+    AddrMode1616,
+    AddrMode1632,
+    AddrModeReal,
+    AddrModeFlat
+} ADDRESS_MODE;
+typedef struct _tagADDRESS64 {
+    DWORD64       Offset;
+    WORD          Segment;
+    ADDRESS_MODE  Mode;
+} ADDRESS64, *LPADDRESS64;
+typedef struct _KDHELP64 {
+    DWORD64   Thread;
+    DWORD   ThCallbackStack;
+    DWORD   ThCallbackBStore;
+    DWORD   NextCallback;
+    DWORD   FramePointer;
+    DWORD64   KiCallUserMode;
+    DWORD64   KeUserCallbackDispatcher;
+    DWORD64   SystemRangeStart;
+    DWORD64  Reserved[8];
+} KDHELP64, *PKDHELP64;
+typedef struct _tagSTACKFRAME64 {
+    ADDRESS64   AddrPC;               // program counter
+    ADDRESS64   AddrReturn;           // return address
+    ADDRESS64   AddrFrame;            // frame pointer
+    ADDRESS64   AddrStack;            // stack pointer
+    ADDRESS64   AddrBStore;           // backing store pointer
+    PVOID       FuncTableEntry;       // pointer to pdata/fpo or NULL
+    DWORD64     Params[4];            // possible arguments to the function
+    BOOL        Far;                  // WOW far call
+    BOOL        Virtual;              // is this a virtual frame?
+    DWORD64     Reserved[3];
+    KDHELP64    KdHelp;
+} STACKFRAME64, *LPSTACKFRAME64;
+typedef
+BOOL
+(__stdcall *PREAD_PROCESS_MEMORY_ROUTINE64)(
+    HANDLE      hProcess,
+    DWORD64     qwBaseAddress,
+    PVOID       lpBuffer,
+    DWORD       nSize,
+    LPDWORD     lpNumberOfBytesRead
+    );
+typedef
+PVOID
+(__stdcall *PFUNCTION_TABLE_ACCESS_ROUTINE64)(
+    HANDLE  hProcess,
+    DWORD64 AddrBase
+    );
+typedef
+DWORD64
+(__stdcall *PGET_MODULE_BASE_ROUTINE64)(
+    HANDLE  hProcess,
+    DWORD64 Address
+    );
+typedef
+DWORD64
+(__stdcall *PTRANSLATE_ADDRESS_ROUTINE64)(
+    HANDLE    hProcess,
+    HANDLE    hThread,
+    LPADDRESS64 lpaddr
+    );
+#define SYMOPT_CASE_INSENSITIVE         0x00000001
+#define SYMOPT_UNDNAME                  0x00000002
+#define SYMOPT_DEFERRED_LOADS           0x00000004
+#define SYMOPT_NO_CPP                   0x00000008
+#define SYMOPT_LOAD_LINES               0x00000010
+#define SYMOPT_OMAP_FIND_NEAREST        0x00000020
+#define SYMOPT_LOAD_ANYTHING            0x00000040
+#define SYMOPT_IGNORE_CVREC             0x00000080
+#define SYMOPT_NO_UNQUALIFIED_LOADS     0x00000100
+#define SYMOPT_FAIL_CRITICAL_ERRORS     0x00000200
+#define SYMOPT_EXACT_SYMBOLS            0x00000400
+#define SYMOPT_ALLOW_ABSOLUTE_SYMBOLS   0x00000800
+#define SYMOPT_IGNORE_NT_SYMPATH        0x00001000
+#define SYMOPT_INCLUDE_32BIT_MODULES    0x00002000
+#define SYMOPT_PUBLICS_ONLY             0x00004000
+#define SYMOPT_NO_PUBLICS               0x00008000
+#define SYMOPT_AUTO_PUBLICS             0x00010000
+#define SYMOPT_NO_IMAGE_SEARCH          0x00020000
+#define SYMOPT_SECURE                   0x00040000
+#define SYMOPT_DEBUG                    0x80000000
+#define UNDNAME_COMPLETE                 (0x0000)  // Enable full undecoration
+#define UNDNAME_NAME_ONLY                (0x1000)  // Crack only the name for primary declaration;
+#endif  // _MSC_VER < 1300
+#pragma pack(pop)
+
+// Some missing defines (for VC5/6):
+#ifndef INVALID_FILE_ATTRIBUTES
+#define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
+#endif  
+
+
+// secure-CRT_functions are only available starting with VC8
+#if _MSC_VER < 1400
+#define strcpy_s(dst, len, src) strcpy(dst, src)
+#define strncpy_s(dst, len, src, maxLen) strncpy(dst, len, src)
+#define strcat_s(dst, len, src) strcat(dst, src)
+#define _snprintf_s _snprintf
+#define _tcscat_s _tcscat
+#endif
+
+static void MyStrCpy(char* szDest, size_t nMaxDestSize, const char* szSrc)
+{
+  if (nMaxDestSize <= 0) return;
+  strncpy_s(szDest, nMaxDestSize, szSrc, _TRUNCATE);
+  szDest[nMaxDestSize-1] = 0;  // INFO: _TRUNCATE will ensure that it is nul-terminated; but with older compilers (<1400) it uses "strncpy" and this does not!)
+}  // MyStrCpy
+
+// Normally it should be enough to use 'CONTEXT_FULL' (better would be 'CONTEXT_ALL')
+#define USED_CONTEXT_FLAGS CONTEXT_FULL
+
+
+class StackWalkerInternal
+{
+public:
+  StackWalkerInternal(StackWalker *parent, HANDLE hProcess)
+  {
+    m_parent = parent;
+    m_hDbhHelp = NULL;
+    pSC = NULL;
+    m_hProcess = hProcess;
+    m_szSymPath = NULL;
+    pSFTA = NULL;
+    pSGLFA = NULL;
+    pSGMB = NULL;
+    pSGMI = NULL;
+    pSGO = NULL;
+    pSGSFA = NULL;
+    pSI = NULL;
+    pSLM = NULL;
+    pSSO = NULL;
+    pSW = NULL;
+    pUDSN = NULL;
+    pSGSP = NULL;
+  }
+  ~StackWalkerInternal()
+  {
+    if (pSC != NULL)
+      pSC(m_hProcess);  // SymCleanup
+    if (m_hDbhHelp != NULL)
+      FreeLibrary(m_hDbhHelp);
+    m_hDbhHelp = NULL;
+    m_parent = NULL;
+    if(m_szSymPath != NULL)
+      free(m_szSymPath);
+    m_szSymPath = NULL;
+  }
+  BOOL Init(LPCSTR szSymPath)
+  {
+    if (m_parent == NULL)
+      return FALSE;
+    // Dynamically load the Entry-Points for dbghelp.dll:
+    // First try to load the newsest one from
+    TCHAR szTemp[4096];
+    // But before wqe do this, we first check if the ".local" file exists
+    if (GetModuleFileName(NULL, szTemp, 4096) > 0)
+    {
+      _tcscat_s(szTemp, _T(".local"));
+      if (GetFileAttributes(szTemp) == INVALID_FILE_ATTRIBUTES)
+      {
+        // ".local" file does not exist, so we can try to load the dbghelp.dll from the "Debugging Tools for Windows"
+        // Ok, first try the new path according to the archtitecture:
+#ifdef _M_IX86
+        if ( (m_hDbhHelp == NULL) && (GetEnvironmentVariable(_T("ProgramFiles"), szTemp, 4096) > 0) )
+        {
+          _tcscat_s(szTemp, _T("\\Debugging Tools for Windows (x86)\\dbghelp.dll"));
+          // now check if the file exists:
+          if (GetFileAttributes(szTemp) != INVALID_FILE_ATTRIBUTES)
+          {
+            m_hDbhHelp = LoadLibrary(szTemp);
+          }
+        }
+#elif _M_X64
+        if ( (m_hDbhHelp == NULL) && (GetEnvironmentVariable(_T("ProgramFiles"), szTemp, 4096) > 0) )
+        {
+          _tcscat_s(szTemp, _T("\\Debugging Tools for Windows (x64)\\dbghelp.dll"));
+          // now check if the file exists:
+          if (GetFileAttributes(szTemp) != INVALID_FILE_ATTRIBUTES)
+          {
+            m_hDbhHelp = LoadLibrary(szTemp);
+          }
+        }
+#elif _M_IA64
+        if ( (m_hDbhHelp == NULL) && (GetEnvironmentVariable(_T("ProgramFiles"), szTemp, 4096) > 0) )
+        {
+          _tcscat_s(szTemp, _T("\\Debugging Tools for Windows (ia64)\\dbghelp.dll"));
+          // now check if the file exists:
+          if (GetFileAttributes(szTemp) != INVALID_FILE_ATTRIBUTES)
+          {
+            m_hDbhHelp = LoadLibrary(szTemp);
+          }
+        }
+#endif
+        // If still not found, try the old directories...
+        if ( (m_hDbhHelp == NULL) && (GetEnvironmentVariable(_T("ProgramFiles"), szTemp, 4096) > 0) )
+        {
+          _tcscat_s(szTemp, _T("\\Debugging Tools for Windows\\dbghelp.dll"));
+          // now check if the file exists:
+          if (GetFileAttributes(szTemp) != INVALID_FILE_ATTRIBUTES)
+          {
+            m_hDbhHelp = LoadLibrary(szTemp);
+          }
+        }
+#if defined _M_X64 || defined _M_IA64
+        // Still not found? Then try to load the (old) 64-Bit version:
+        if ( (m_hDbhHelp == NULL) && (GetEnvironmentVariable(_T("ProgramFiles"), szTemp, 4096) > 0) )
+        {
+          _tcscat_s(szTemp, _T("\\Debugging Tools for Windows 64-Bit\\dbghelp.dll"));
+          if (GetFileAttributes(szTemp) != INVALID_FILE_ATTRIBUTES)
+          {
+            m_hDbhHelp = LoadLibrary(szTemp);
+          }
+        }
+#endif
+      }
+    }
+    if (m_hDbhHelp == NULL)  // if not already loaded, try to load a default-one
+      m_hDbhHelp = LoadLibrary( _T("dbghelp.dll") );
+    if (m_hDbhHelp == NULL)
+      return FALSE;
+    pSI = (tSI) GetProcAddress(m_hDbhHelp, "SymInitialize" );
+    pSC = (tSC) GetProcAddress(m_hDbhHelp, "SymCleanup" );
+
+    pSW = (tSW) GetProcAddress(m_hDbhHelp, "StackWalk64" );
+    pSGO = (tSGO) GetProcAddress(m_hDbhHelp, "SymGetOptions" );
+    pSSO = (tSSO) GetProcAddress(m_hDbhHelp, "SymSetOptions" );
+
+    pSFTA = (tSFTA) GetProcAddress(m_hDbhHelp, "SymFunctionTableAccess64" );
+    pSGLFA = (tSGLFA) GetProcAddress(m_hDbhHelp, "SymGetLineFromAddr64" );
+    pSGMB = (tSGMB) GetProcAddress(m_hDbhHelp, "SymGetModuleBase64" );
+    pSGMI = (tSGMI) GetProcAddress(m_hDbhHelp, "SymGetModuleInfo64" );
+    pSGSFA = (tSGSFA) GetProcAddress(m_hDbhHelp, "SymGetSymFromAddr64" );
+    pUDSN = (tUDSN) GetProcAddress(m_hDbhHelp, "UnDecorateSymbolName" );
+    pSLM = (tSLM) GetProcAddress(m_hDbhHelp, "SymLoadModule64" );
+    pSGSP =(tSGSP) GetProcAddress(m_hDbhHelp, "SymGetSearchPath" );
+
+    if ( pSC == NULL || pSFTA == NULL || pSGMB == NULL || pSGMI == NULL ||
+      pSGO == NULL || pSGSFA == NULL || pSI == NULL || pSSO == NULL ||
+      pSW == NULL || pUDSN == NULL || pSLM == NULL )
+    {
+      FreeLibrary(m_hDbhHelp);
+      m_hDbhHelp = NULL;
+      pSC = NULL;
+      return FALSE;
+    }
+
+    // SymInitialize
+    if (szSymPath != NULL)
+      m_szSymPath = _strdup(szSymPath);
+    if (this->pSI(m_hProcess, m_szSymPath, FALSE) == FALSE)
+      this->m_parent->OnDbgHelpErr("SymInitialize", GetLastError(), 0);
+      
+    DWORD symOptions = this->pSGO();  // SymGetOptions
+    symOptions |= SYMOPT_LOAD_LINES;
+    symOptions |= SYMOPT_FAIL_CRITICAL_ERRORS;
+    //symOptions |= SYMOPT_NO_PROMPTS;
+    // SymSetOptions
+    symOptions = this->pSSO(symOptions);
+
+    char buf[StackWalker::STACKWALK_MAX_NAMELEN] = {0};
+    if (this->pSGSP != NULL)
+    {
+      if (this->pSGSP(m_hProcess, buf, StackWalker::STACKWALK_MAX_NAMELEN) == FALSE)
+        this->m_parent->OnDbgHelpErr("SymGetSearchPath", GetLastError(), 0);
+    }
+    char szUserName[1024] = {0};
+    DWORD dwSize = 1024;
+    GetUserNameA(szUserName, &dwSize);
+    this->m_parent->OnSymInit(buf, symOptions, szUserName);
+
+    return TRUE;
+  }
+
+  StackWalker *m_parent;
+
+  HMODULE m_hDbhHelp;
+  HANDLE m_hProcess;
+  LPSTR m_szSymPath;
+
+#pragma pack(push,8)
+typedef struct IMAGEHLP_MODULE64_V3 {
+    DWORD    SizeOfStruct;           // set to sizeof(IMAGEHLP_MODULE64)
+    DWORD64  BaseOfImage;            // base load address of module
+    DWORD    ImageSize;              // virtual size of the loaded module
+    DWORD    TimeDateStamp;          // date/time stamp from pe header
+    DWORD    CheckSum;               // checksum from the pe header
+    DWORD    NumSyms;                // number of symbols in the symbol table
+    SYM_TYPE SymType;                // type of symbols loaded
+    CHAR     ModuleName[32];         // module name
+    CHAR     ImageName[256];         // image name
+    CHAR     LoadedImageName[256];   // symbol file name
+    // new elements: 07-Jun-2002
+    CHAR     LoadedPdbName[256];     // pdb file name
+    DWORD    CVSig;                  // Signature of the CV record in the debug directories
+    CHAR     CVData[MAX_PATH * 3];   // Contents of the CV record
+    DWORD    PdbSig;                 // Signature of PDB
+    GUID     PdbSig70;               // Signature of PDB (VC 7 and up)
+    DWORD    PdbAge;                 // DBI age of pdb
+    BOOL     PdbUnmatched;           // loaded an unmatched pdb
+    BOOL     DbgUnmatched;           // loaded an unmatched dbg
+    BOOL     LineNumbers;            // we have line number information
+    BOOL     GlobalSymbols;          // we have internal symbol information
+    BOOL     TypeInfo;               // we have type information
+    // new elements: 17-Dec-2003
+    BOOL     SourceIndexed;          // pdb supports source server
+    BOOL     Publics;                // contains public symbols
+};
+
+typedef struct IMAGEHLP_MODULE64_V2 {
+    DWORD    SizeOfStruct;           // set to sizeof(IMAGEHLP_MODULE64)
+    DWORD64  BaseOfImage;            // base load address of module
+    DWORD    ImageSize;              // virtual size of the loaded module
+    DWORD    TimeDateStamp;          // date/time stamp from pe header
+    DWORD    CheckSum;               // checksum from the pe header
+    DWORD    NumSyms;                // number of symbols in the symbol table
+    SYM_TYPE SymType;                // type of symbols loaded
+    CHAR     ModuleName[32];         // module name
+    CHAR     ImageName[256];         // image name
+    CHAR     LoadedImageName[256];   // symbol file name
+};
+#pragma pack(pop)
+
+
+  // SymCleanup()
+  typedef BOOL (__stdcall *tSC)( IN HANDLE hProcess );
+  tSC pSC;
+
+  // SymFunctionTableAccess64()
+  typedef PVOID (__stdcall *tSFTA)( HANDLE hProcess, DWORD64 AddrBase );
+  tSFTA pSFTA;
+
+  // SymGetLineFromAddr64()
+  typedef BOOL (__stdcall *tSGLFA)( IN HANDLE hProcess, IN DWORD64 dwAddr,
+    OUT PDWORD pdwDisplacement, OUT PIMAGEHLP_LINE64 Line );
+  tSGLFA pSGLFA;
+
+  // SymGetModuleBase64()
+  typedef DWORD64 (__stdcall *tSGMB)( IN HANDLE hProcess, IN DWORD64 dwAddr );
+  tSGMB pSGMB;
+
+  // SymGetModuleInfo64()
+  typedef BOOL (__stdcall *tSGMI)( IN HANDLE hProcess, IN DWORD64 dwAddr, OUT IMAGEHLP_MODULE64_V3 *ModuleInfo );
+  tSGMI pSGMI;
+
+  // SymGetOptions()
+  typedef DWORD (__stdcall *tSGO)( VOID );
+  tSGO pSGO;
+
+  // SymGetSymFromAddr64()
+  typedef BOOL (__stdcall *tSGSFA)( IN HANDLE hProcess, IN DWORD64 dwAddr,
+    OUT PDWORD64 pdwDisplacement, OUT PIMAGEHLP_SYMBOL64 Symbol );
+  tSGSFA pSGSFA;
+
+  // SymInitialize()
+  typedef BOOL (__stdcall *tSI)( IN HANDLE hProcess, IN PSTR UserSearchPath, IN BOOL fInvadeProcess );
+  tSI pSI;
+
+  // SymLoadModule64()
+  typedef DWORD64 (__stdcall *tSLM)( IN HANDLE hProcess, IN HANDLE hFile,
+    IN PSTR ImageName, IN PSTR ModuleName, IN DWORD64 BaseOfDll, IN DWORD SizeOfDll );
+  tSLM pSLM;
+
+  // SymSetOptions()
+  typedef DWORD (__stdcall *tSSO)( IN DWORD SymOptions );
+  tSSO pSSO;
+
+  // StackWalk64()
+  typedef BOOL (__stdcall *tSW)( 
+    DWORD MachineType, 
+    HANDLE hProcess,
+    HANDLE hThread, 
+    LPSTACKFRAME64 StackFrame, 
+    PVOID ContextRecord,
+    PREAD_PROCESS_MEMORY_ROUTINE64 ReadMemoryRoutine,
+    PFUNCTION_TABLE_ACCESS_ROUTINE64 FunctionTableAccessRoutine,
+    PGET_MODULE_BASE_ROUTINE64 GetModuleBaseRoutine,
+    PTRANSLATE_ADDRESS_ROUTINE64 TranslateAddress );
+  tSW pSW;
+
+  // UnDecorateSymbolName()
+  typedef DWORD (__stdcall WINAPI *tUDSN)( PCSTR DecoratedName, PSTR UnDecoratedName,
+    DWORD UndecoratedLength, DWORD Flags );
+  tUDSN pUDSN;
+
+  typedef BOOL (__stdcall WINAPI *tSGSP)(HANDLE hProcess, PSTR SearchPath, DWORD SearchPathLength);
+  tSGSP pSGSP;
+
+
+private:
+  // **************************************** ToolHelp32 ************************
+  #define MAX_MODULE_NAME32 255
+  #define TH32CS_SNAPMODULE   0x00000008
+  #pragma pack( push, 8 )
+  typedef struct tagMODULEENTRY32
+  {
+      DWORD   dwSize;
+      DWORD   th32ModuleID;       // This module
+      DWORD   th32ProcessID;      // owning process
+      DWORD   GlblcntUsage;       // Global usage count on the module
+      DWORD   ProccntUsage;       // Module usage count in th32ProcessID's context
+      BYTE  * modBaseAddr;        // Base address of module in th32ProcessID's context
+      DWORD   modBaseSize;        // Size in bytes of module starting at modBaseAddr
+      HMODULE hModule;            // The hModule of this module in th32ProcessID's context
+      char    szModule[MAX_MODULE_NAME32 + 1];
+      char    szExePath[MAX_PATH];
+  } MODULEENTRY32;
+  typedef MODULEENTRY32 *  PMODULEENTRY32;
+  typedef MODULEENTRY32 *  LPMODULEENTRY32;
+  #pragma pack( pop )
+
+  BOOL GetModuleListTH32(HANDLE hProcess, DWORD pid)
+  {
+    // CreateToolhelp32Snapshot()
+    typedef HANDLE (__stdcall *tCT32S)(DWORD dwFlags, DWORD th32ProcessID);
+    // Module32First()
+    typedef BOOL (__stdcall *tM32F)(HANDLE hSnapshot, LPMODULEENTRY32 lpme);
+    // Module32Next()
+    typedef BOOL (__stdcall *tM32N)(HANDLE hSnapshot, LPMODULEENTRY32 lpme);
+
+    // try both dlls...
+    const TCHAR *dllname[] = { _T("kernel32.dll"), _T("tlhelp32.dll") };
+    HINSTANCE hToolhelp = NULL;
+    tCT32S pCT32S = NULL;
+    tM32F pM32F = NULL;
+    tM32N pM32N = NULL;
+
+    HANDLE hSnap;
+    MODULEENTRY32 me;
+    me.dwSize = sizeof(me);
+    BOOL keepGoing;
+    size_t i;
+
+    for (i = 0; i<(sizeof(dllname) / sizeof(dllname[0])); i++ )
+    {
+      hToolhelp = LoadLibrary( dllname[i] );
+      if (hToolhelp == NULL)
+        continue;
+      pCT32S = (tCT32S) GetProcAddress(hToolhelp, "CreateToolhelp32Snapshot");
+      pM32F = (tM32F) GetProcAddress(hToolhelp, "Module32First");
+      pM32N = (tM32N) GetProcAddress(hToolhelp, "Module32Next");
+      if ( (pCT32S != NULL) && (pM32F != NULL) && (pM32N != NULL) )
+        break; // found the functions!
+      FreeLibrary(hToolhelp);
+      hToolhelp = NULL;
+    }
+
+    if (hToolhelp == NULL)
+      return FALSE;
+
+    hSnap = pCT32S( TH32CS_SNAPMODULE, pid );
+    if (hSnap == (HANDLE) -1)
+    {
+      FreeLibrary(hToolhelp);
+      return FALSE;
+    }
+
+    keepGoing = !!pM32F( hSnap, &me );
+    int cnt = 0;
+    while (keepGoing)
+    {
+      this->LoadModule(hProcess, me.szExePath, me.szModule, (DWORD64) me.modBaseAddr, me.modBaseSize);
+      cnt++;
+      keepGoing = !!pM32N( hSnap, &me );
+    }
+    CloseHandle(hSnap);
+    FreeLibrary(hToolhelp);
+    if (cnt <= 0)
+      return FALSE;
+    return TRUE;
+  }  // GetModuleListTH32
+
+  // **************************************** PSAPI ************************
+  typedef struct _MODULEINFO {
+      LPVOID lpBaseOfDll;
+      DWORD SizeOfImage;
+      LPVOID EntryPoint;
+  } MODULEINFO, *LPMODULEINFO;
+
+  BOOL GetModuleListPSAPI(HANDLE hProcess)
+  {
+    // EnumProcessModules()
+    typedef BOOL (__stdcall *tEPM)(HANDLE hProcess, HMODULE *lphModule, DWORD cb, LPDWORD lpcbNeeded );
+    // GetModuleFileNameEx()
+    typedef DWORD (__stdcall *tGMFNE)(HANDLE hProcess, HMODULE hModule, LPSTR lpFilename, DWORD nSize );
+    // GetModuleBaseName()
+    typedef DWORD (__stdcall *tGMBN)(HANDLE hProcess, HMODULE hModule, LPSTR lpFilename, DWORD nSize );
+    // GetModuleInformation()
+    typedef BOOL (__stdcall *tGMI)(HANDLE hProcess, HMODULE hModule, LPMODULEINFO pmi, DWORD nSize );
+
+    HINSTANCE hPsapi;
+    tEPM pEPM;
+    tGMFNE pGMFNE;
+    tGMBN pGMBN;
+    tGMI pGMI;
+
+    DWORD i;
+    //ModuleEntry e;
+    DWORD cbNeeded;
+    MODULEINFO mi;
+    HMODULE *hMods = 0;
+    char *tt = NULL;
+    char *tt2 = NULL;
+    const SIZE_T TTBUFLEN = 8096;
+    int cnt = 0;
+
+    hPsapi = LoadLibrary( _T("psapi.dll") );
+    if (hPsapi == NULL)
+      return FALSE;
+
+    pEPM = (tEPM) GetProcAddress( hPsapi, "EnumProcessModules" );
+    pGMFNE = (tGMFNE) GetProcAddress( hPsapi, "GetModuleFileNameExA" );
+    pGMBN = (tGMFNE) GetProcAddress( hPsapi, "GetModuleBaseNameA" );
+    pGMI = (tGMI) GetProcAddress( hPsapi, "GetModuleInformation" );
+    if ( (pEPM == NULL) || (pGMFNE == NULL) || (pGMBN == NULL) || (pGMI == NULL) )
+    {
+      // we couldn´t find all functions
+      FreeLibrary(hPsapi);
+      return FALSE;
+    }
+
+    hMods = (HMODULE*) malloc(sizeof(HMODULE) * (TTBUFLEN / sizeof(HMODULE)));
+    tt = (char*) malloc(sizeof(char) * TTBUFLEN);
+    tt2 = (char*) malloc(sizeof(char) * TTBUFLEN);
+    if ( (hMods == NULL) || (tt == NULL) || (tt2 == NULL) )
+      goto cleanup;
+
+    if ( ! pEPM( hProcess, hMods, TTBUFLEN, &cbNeeded ) )
+    {
+      //_ftprintf(fLogFile, _T("%lu: EPM failed, GetLastError = %lu\n"), g_dwShowCount, gle );
+      goto cleanup;
+    }
+
+    if ( cbNeeded > TTBUFLEN )
+    {
+      //_ftprintf(fLogFile, _T("%lu: More than %lu module handles. Huh?\n"), g_dwShowCount, lenof( hMods ) );
+      goto cleanup;
+    }
+
+    for ( i = 0; i < cbNeeded / sizeof(hMods[0]); i++ )
+    {
+      // base address, size
+      pGMI(hProcess, hMods[i], &mi, sizeof(mi));
+      // image file name
+      tt[0] = 0;
+      pGMFNE(hProcess, hMods[i], tt, TTBUFLEN );
+      // module name
+      tt2[0] = 0;
+      pGMBN(hProcess, hMods[i], tt2, TTBUFLEN );
+
+      DWORD dwRes = this->LoadModule(hProcess, tt, tt2, (DWORD64) mi.lpBaseOfDll, mi.SizeOfImage);
+      if (dwRes != ERROR_SUCCESS)
+        this->m_parent->OnDbgHelpErr("LoadModule", dwRes, 0);
+      cnt++;
+    }
+
+  cleanup:
+    if (hPsapi != NULL) FreeLibrary(hPsapi);
+    if (tt2 != NULL) free(tt2);
+    if (tt != NULL) free(tt);
+    if (hMods != NULL) free(hMods);
+
+    return cnt != 0;
+  }  // GetModuleListPSAPI
+
+  DWORD LoadModule(HANDLE hProcess, LPCSTR img, LPCSTR mod, DWORD64 baseAddr, DWORD size)
+  {
+    CHAR *szImg = _strdup(img);
+    CHAR *szMod = _strdup(mod);
+    DWORD result = ERROR_SUCCESS;
+    if ( (szImg == NULL) || (szMod == NULL) )
+      result = ERROR_NOT_ENOUGH_MEMORY;
+    else
+    {
+      if (pSLM(hProcess, 0, szImg, szMod, baseAddr, size) == 0)
+        result = GetLastError();
+    }
+    ULONGLONG fileVersion = 0;
+    if ( (m_parent != NULL) && (szImg != NULL) )
+    {
+      // try to retrive the file-version:
+      if ( (this->m_parent->m_options & StackWalker::RetrieveFileVersion) != 0)
+      {
+        VS_FIXEDFILEINFO *fInfo = NULL;
+        DWORD dwHandle;
+        DWORD dwSize = GetFileVersionInfoSizeA(szImg, &dwHandle);
+        if (dwSize > 0)
+        {
+          LPVOID vData = malloc(dwSize);
+          if (vData != NULL)
+          {
+            if (GetFileVersionInfoA(szImg, dwHandle, dwSize, vData) != 0)
+            {
+              UINT len;
+              TCHAR szSubBlock[] = _T("\\");
+              if (VerQueryValue(vData, szSubBlock, (LPVOID*) &fInfo, &len) == 0)
+                fInfo = NULL;
+              else
+              {
+                fileVersion = ((ULONGLONG)fInfo->dwFileVersionLS) + ((ULONGLONG)fInfo->dwFileVersionMS << 32);
+              }
+            }
+            free(vData);
+          }
+        }
+      }
+
+      // Retrive some additional-infos about the module
+      IMAGEHLP_MODULE64_V3 Module;
+      const char *szSymType = "-unknown-";
+      if (this->GetModuleInfo(hProcess, baseAddr, &Module) != FALSE)
+      {
+        switch(Module.SymType)
+        {
+          case SymNone:
+            szSymType = "-nosymbols-";
+            break;
+          case SymCoff:  // 1
+            szSymType = "COFF";
+            break;
+          case SymCv:  // 2
+            szSymType = "CV";
+            break;
+          case SymPdb:  // 3
+            szSymType = "PDB";
+            break;
+          case SymExport:  // 4
+            szSymType = "-exported-";
+            break;
+          case SymDeferred:  // 5
+            szSymType = "-deferred-";
+            break;
+          case SymSym:  // 6
+            szSymType = "SYM";
+            break;
+          case 7: // SymDia:
+            szSymType = "DIA";
+            break;
+          case 8: //SymVirtual:
+            szSymType = "Virtual";
+            break;
+        }
+      }
+      LPCSTR pdbName = Module.LoadedImageName;
+      if (Module.LoadedPdbName[0] != 0)
+        pdbName = Module.LoadedPdbName;
+      this->m_parent->OnLoadModule(img, mod, baseAddr, size, result, szSymType, pdbName, fileVersion);
+    }
+    if (szImg != NULL) free(szImg);
+    if (szMod != NULL) free(szMod);
+    return result;
+  }
+public:
+  BOOL LoadModules(HANDLE hProcess, DWORD dwProcessId)
+  {
+    // first try toolhelp32
+    if (GetModuleListTH32(hProcess, dwProcessId))
+      return true;
+    // then try psapi
+    return GetModuleListPSAPI(hProcess);
+  }
+
+
+  BOOL GetModuleInfo(HANDLE hProcess, DWORD64 baseAddr, IMAGEHLP_MODULE64_V3 *pModuleInfo)
+  {
+    memset(pModuleInfo, 0, sizeof(IMAGEHLP_MODULE64_V3));
+    if(this->pSGMI == NULL)
+    {
+      SetLastError(ERROR_DLL_INIT_FAILED);
+      return FALSE;
+    }
+    // First try to use the larger ModuleInfo-Structure
+    pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V3);
+    void *pData = malloc(4096); // reserve enough memory, so the bug in v6.3.5.1 does not lead to memory-overwrites...
+    if (pData == NULL)
+    {
+      SetLastError(ERROR_NOT_ENOUGH_MEMORY);
+      return FALSE;
+    }
+    memcpy(pData, pModuleInfo, sizeof(IMAGEHLP_MODULE64_V3));
+    static bool s_useV3Version = true;
+    if (s_useV3Version)
+    {
+      if (this->pSGMI(hProcess, baseAddr, (IMAGEHLP_MODULE64_V3*) pData) != FALSE)
+      {
+        // only copy as much memory as is reserved...
+        memcpy(pModuleInfo, pData, sizeof(IMAGEHLP_MODULE64_V3));
+        pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V3);
+        free(pData);
+        return TRUE;
+      }
+      s_useV3Version = false;  // to prevent unneccessarry calls with the larger struct...
+    }
+
+    // could not retrive the bigger structure, try with the smaller one (as defined in VC7.1)...
+    pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V2);
+    memcpy(pData, pModuleInfo, sizeof(IMAGEHLP_MODULE64_V2));
+    if (this->pSGMI(hProcess, baseAddr, (IMAGEHLP_MODULE64_V3*) pData) != FALSE)
+    {
+      // only copy as much memory as is reserved...
+      memcpy(pModuleInfo, pData, sizeof(IMAGEHLP_MODULE64_V2));
+      pModuleInfo->SizeOfStruct = sizeof(IMAGEHLP_MODULE64_V2);
+      free(pData);
+      return TRUE;
+    }
+    free(pData);
+    SetLastError(ERROR_DLL_INIT_FAILED);
+    return FALSE;
+  }
+};
+
+// #############################################################
+StackWalker::StackWalker(DWORD dwProcessId, HANDLE hProcess)
+{
+  this->m_verbose = true;
+  this->m_options = OptionsAll;
+  this->m_modulesLoaded = FALSE;
+  this->m_hProcess = hProcess;
+  this->m_sw = new StackWalkerInternal(this, this->m_hProcess);
+  this->m_dwProcessId = dwProcessId;
+  this->m_szSymPath = NULL;
+  this->m_MaxRecursionCount = 1000;
+}
+StackWalker::StackWalker(bool verbose, int options, LPCSTR szSymPath, DWORD dwProcessId, HANDLE hProcess)
+{
+  this->m_verbose = verbose;
+  this->m_options = options;
+  this->m_modulesLoaded = FALSE;
+  this->m_hProcess = hProcess;
+  this->m_sw = new StackWalkerInternal(this, this->m_hProcess);
+  this->m_dwProcessId = dwProcessId;
+  if (szSymPath != NULL)
+  {
+    this->m_szSymPath = _strdup(szSymPath);
+    this->m_options |= SymBuildPath;
+  }
+  else
+    this->m_szSymPath = NULL;
+  this->m_MaxRecursionCount = 1000;
+}
+
+StackWalker::~StackWalker()
+{
+  if (m_szSymPath != NULL)
+    free(m_szSymPath);
+  m_szSymPath = NULL;
+  if (this->m_sw != NULL)
+    delete this->m_sw;
+  this->m_sw = NULL;
+}
+
+BOOL StackWalker::LoadModules()
+{
+  if (this->m_sw == NULL)
+  {
+    SetLastError(ERROR_DLL_INIT_FAILED);
+    return FALSE;
+  }
+  if (m_modulesLoaded != FALSE)
+    return TRUE;
+
+  // Build the sym-path:
+  char *szSymPath = NULL;
+  if ( (this->m_options & SymBuildPath) != 0)
+  {
+    const size_t nSymPathLen = 4096;
+    szSymPath = (char*) malloc(nSymPathLen);
+    if (szSymPath == NULL)
+    {
+      SetLastError(ERROR_NOT_ENOUGH_MEMORY);
+      return FALSE;
+    }
+    szSymPath[0] = 0;
+    // Now first add the (optional) provided sympath:
+    if (this->m_szSymPath != NULL)
+    {
+      strcat_s(szSymPath, nSymPathLen, this->m_szSymPath);
+      strcat_s(szSymPath, nSymPathLen, ";");
+    }
+
+    strcat_s(szSymPath, nSymPathLen, ".;");
+
+    const size_t nTempLen = 1024;
+    char szTemp[nTempLen];
+    // Now add the current directory:
+    if (GetCurrentDirectoryA(nTempLen, szTemp) > 0)
+    {
+      szTemp[nTempLen-1] = 0;
+      strcat_s(szSymPath, nSymPathLen, szTemp);
+      strcat_s(szSymPath, nSymPathLen, ";");
+    }
+
+    // Now add the path for the main-module:
+    if (GetModuleFileNameA(NULL, szTemp, nTempLen) > 0)
+    {
+      szTemp[nTempLen-1] = 0;
+      for (char *p = (szTemp+strlen(szTemp)-1); p >= szTemp; --p)
+      {
+        // locate the rightmost path separator
+        if ( (*p == '\\') || (*p == '/') || (*p == ':') )
+        {
+          *p = 0;
+          break;
+        }
+      }  // for (search for path separator...)
+      if (strlen(szTemp) > 0)
+      {
+        strcat_s(szSymPath, nSymPathLen, szTemp);
+        strcat_s(szSymPath, nSymPathLen, ";");
+      }
+    }
+    if (GetEnvironmentVariableA("_NT_SYMBOL_PATH", szTemp, nTempLen) > 0)
+    {
+      szTemp[nTempLen-1] = 0;
+      strcat_s(szSymPath, nSymPathLen, szTemp);
+      strcat_s(szSymPath, nSymPathLen, ";");
+    }
+    if (GetEnvironmentVariableA("_NT_ALTERNATE_SYMBOL_PATH", szTemp, nTempLen) > 0)
+    {
+      szTemp[nTempLen-1] = 0;
+      strcat_s(szSymPath, nSymPathLen, szTemp);
+      strcat_s(szSymPath, nSymPathLen, ";");
+    }
+    if (GetEnvironmentVariableA("SYSTEMROOT", szTemp, nTempLen) > 0)
+    {
+      szTemp[nTempLen-1] = 0;
+      strcat_s(szSymPath, nSymPathLen, szTemp);
+      strcat_s(szSymPath, nSymPathLen, ";");
+      // also add the "system32"-directory:
+      strcat_s(szTemp, nTempLen, "\\system32");
+      strcat_s(szSymPath, nSymPathLen, szTemp);
+      strcat_s(szSymPath, nSymPathLen, ";");
+    }
+
+    if ( (this->m_options & SymUseSymSrv) != 0)
+    {
+      if (GetEnvironmentVariableA("SYSTEMDRIVE", szTemp, nTempLen) > 0)
+      {
+        szTemp[nTempLen-1] = 0;
+        strcat_s(szSymPath, nSymPathLen, "SRV*");
+        strcat_s(szSymPath, nSymPathLen, szTemp);
+        strcat_s(szSymPath, nSymPathLen, "\\websymbols");
+        strcat_s(szSymPath, nSymPathLen, "*http://msdl.microsoft.com/download/symbols;");
+      }
+      else
+        strcat_s(szSymPath, nSymPathLen, "SRV*c:\\websymbols*http://msdl.microsoft.com/download/symbols;");
+    }
+  }  // if SymBuildPath
+
+  // First Init the whole stuff...
+  BOOL bRet = this->m_sw->Init(szSymPath);
+  if (szSymPath != NULL) free(szSymPath); szSymPath = NULL;
+  if (bRet == FALSE)
+  {
+    this->OnDbgHelpErr("Error while initializing dbghelp.dll", 0, 0);
+    SetLastError(ERROR_DLL_INIT_FAILED);
+    return FALSE;
+  }
+
+  bRet = this->m_sw->LoadModules(this->m_hProcess, this->m_dwProcessId);
+  if (bRet != FALSE)
+    m_modulesLoaded = TRUE;
+  return bRet;
+}
+
+
+// The following is used to pass the "userData"-Pointer to the user-provided readMemoryFunction
+// This has to be done due to a problem with the "hProcess"-parameter in x64...
+// Because this class is in no case multi-threading-enabled (because of the limitations 
+// of dbghelp.dll) it is "safe" to use a static-variable
+static StackWalker::PReadProcessMemoryRoutine s_readMemoryFunction = NULL;
+static LPVOID s_readMemoryFunction_UserData = NULL;
+
+BOOL StackWalker::ShowCallstack(bool verbose, HANDLE hThread, const CONTEXT *context, PReadProcessMemoryRoutine readMemoryFunction, LPVOID pUserData)
+{
+  m_verbose = verbose;
+  CONTEXT c;
+  CallstackEntry csEntry;
+  IMAGEHLP_SYMBOL64 *pSym = NULL;
+  StackWalkerInternal::IMAGEHLP_MODULE64_V3 Module;
+  IMAGEHLP_LINE64 Line;
+  int frameNum;
+  bool bLastEntryCalled = true;
+  int curRecursionCount = 0;
+
+  if (m_modulesLoaded == FALSE)
+    this->LoadModules();  // ignore the result...
+
+  if (this->m_sw->m_hDbhHelp == NULL)
+  {
+    SetLastError(ERROR_DLL_INIT_FAILED);
+    return FALSE;
+  }
+
+  s_readMemoryFunction = readMemoryFunction;
+  s_readMemoryFunction_UserData = pUserData;
+
+  if (context == NULL)
+  {
+    // If no context is provided, capture the context
+    // See: https://stackwalker.codeplex.com/discussions/446958
+#if _WIN32_WINNT <= 0x0501
+      // If we need to support XP, we need to use the "old way", because "GetThreadId" is not available!
+    if (hThread == GetCurrentThread())
+#else
+    if (GetThreadId(hThread) == GetCurrentThreadId())
+#endif
+    {
+      GET_CURRENT_CONTEXT_STACKWALKER_CODEPLEX(c, USED_CONTEXT_FLAGS);
+    }
+    else
+    {
+      SuspendThread(hThread);
+      memset(&c, 0, sizeof(CONTEXT));
+      c.ContextFlags = USED_CONTEXT_FLAGS;
+      if (GetThreadContext(hThread, &c) == FALSE)
+      {
+        ResumeThread(hThread);
+        return FALSE;
+      }
+    }
+  }
+  else
+    c = *context;
+
+  // init STACKFRAME for first call
+  STACKFRAME64 s; // in/out stackframe
+  memset(&s, 0, sizeof(s));
+  DWORD imageType;
+#ifdef _M_IX86
+  // normally, call ImageNtHeader() and use machine info from PE header
+  imageType = IMAGE_FILE_MACHINE_I386;
+  s.AddrPC.Offset = c.Eip;
+  s.AddrPC.Mode = AddrModeFlat;
+  s.AddrFrame.Offset = c.Ebp;
+  s.AddrFrame.Mode = AddrModeFlat;
+  s.AddrStack.Offset = c.Esp;
+  s.AddrStack.Mode = AddrModeFlat;
+#elif _M_X64
+  imageType = IMAGE_FILE_MACHINE_AMD64;
+  s.AddrPC.Offset = c.Rip;
+  s.AddrPC.Mode = AddrModeFlat;
+  s.AddrFrame.Offset = c.Rsp;
+  s.AddrFrame.Mode = AddrModeFlat;
+  s.AddrStack.Offset = c.Rsp;
+  s.AddrStack.Mode = AddrModeFlat;
+#elif _M_IA64
+  imageType = IMAGE_FILE_MACHINE_IA64;
+  s.AddrPC.Offset = c.StIIP;
+  s.AddrPC.Mode = AddrModeFlat;
+  s.AddrFrame.Offset = c.IntSp;
+  s.AddrFrame.Mode = AddrModeFlat;
+  s.AddrBStore.Offset = c.RsBSP;
+  s.AddrBStore.Mode = AddrModeFlat;
+  s.AddrStack.Offset = c.IntSp;
+  s.AddrStack.Mode = AddrModeFlat;
+#else
+#error "Platform not supported!"
+#endif
+
+  pSym = (IMAGEHLP_SYMBOL64 *) malloc(sizeof(IMAGEHLP_SYMBOL64) + STACKWALK_MAX_NAMELEN);
+  if (!pSym) goto cleanup;  // not enough memory...
+  memset(pSym, 0, sizeof(IMAGEHLP_SYMBOL64) + STACKWALK_MAX_NAMELEN);
+  pSym->SizeOfStruct = sizeof(IMAGEHLP_SYMBOL64);
+  pSym->MaxNameLength = STACKWALK_MAX_NAMELEN;
+
+  memset(&Line, 0, sizeof(Line));
+  Line.SizeOfStruct = sizeof(Line);
+
+  memset(&Module, 0, sizeof(Module));
+  Module.SizeOfStruct = sizeof(Module);
+
+  for (frameNum = 0; ; ++frameNum )
+  {
+    // get next stack frame (StackWalk64(), SymFunctionTableAccess64(), SymGetModuleBase64())
+    // if this returns ERROR_INVALID_ADDRESS (487) or ERROR_NOACCESS (998), you can
+    // assume that either you are done, or that the stack is so hosed that the next
+    // deeper frame could not be found.
+    // CONTEXT need not to be suplied if imageTyp is IMAGE_FILE_MACHINE_I386!
+    if ( ! this->m_sw->pSW(imageType, this->m_hProcess, hThread, &s, &c, myReadProcMem, this->m_sw->pSFTA, this->m_sw->pSGMB, NULL) )
+    {
+      // INFO: "StackWalk64" does not set "GetLastError"...
+      this->OnDbgHelpErr("StackWalk64", 0, s.AddrPC.Offset);
+      break;
+    }
+
+    csEntry.offset = s.AddrPC.Offset;
+    csEntry.name[0] = 0;
+    csEntry.undName[0] = 0;
+    csEntry.undFullName[0] = 0;
+    csEntry.offsetFromSmybol = 0;
+    csEntry.offsetFromLine = 0;
+    csEntry.lineFileName[0] = 0;
+    csEntry.lineNumber = 0;
+    csEntry.loadedImageName[0] = 0;
+    csEntry.moduleName[0] = 0;
+    if (s.AddrPC.Offset == s.AddrReturn.Offset)
+    {
+      if ( (this->m_MaxRecursionCount > 0) && (curRecursionCount > m_MaxRecursionCount) )
+      {
+        this->OnDbgHelpErr("StackWalk64-Endless-Callstack!", 0, s.AddrPC.Offset);
+        break;
+      }
+      curRecursionCount++;
+    }
+    else
+      curRecursionCount = 0;
+    if (s.AddrPC.Offset != 0)
+    {
+      // we seem to have a valid PC
+      // show procedure info (SymGetSymFromAddr64())
+      if (this->m_sw->pSGSFA(this->m_hProcess, s.AddrPC.Offset, &(csEntry.offsetFromSmybol), pSym) != FALSE)
+      {
+        MyStrCpy(csEntry.name, STACKWALK_MAX_NAMELEN, pSym->Name);
+        // UnDecorateSymbolName()
+        this->m_sw->pUDSN( pSym->Name, csEntry.undName, STACKWALK_MAX_NAMELEN, UNDNAME_NAME_ONLY );
+        this->m_sw->pUDSN( pSym->Name, csEntry.undFullName, STACKWALK_MAX_NAMELEN, UNDNAME_COMPLETE );
+      }
+      else
+      {
+        this->OnDbgHelpErr("SymGetSymFromAddr64", GetLastError(), s.AddrPC.Offset);
+      }
+
+      // show line number info, NT5.0-method (SymGetLineFromAddr64())
+      if (this->m_sw->pSGLFA != NULL )
+      { // yes, we have SymGetLineFromAddr64()
+        if (this->m_sw->pSGLFA(this->m_hProcess, s.AddrPC.Offset, &(csEntry.offsetFromLine), &Line) != FALSE)
+        {
+          csEntry.lineNumber = Line.LineNumber;
+          MyStrCpy(csEntry.lineFileName, STACKWALK_MAX_NAMELEN, Line.FileName);
+        }
+        else
+        {
+          this->OnDbgHelpErr("SymGetLineFromAddr64", GetLastError(), s.AddrPC.Offset);
+        }
+      } // yes, we have SymGetLineFromAddr64()
+
+      if (m_verbose) // getting module info is very slow, skip unless we're being verbose.
+      {
+          // show module info (SymGetModuleInfo64())
+          if (this->m_sw->GetModuleInfo(this->m_hProcess, s.AddrPC.Offset, &Module ) != FALSE)
+          { // got module info OK
+              switch ( Module.SymType )
+              {
+                  case SymNone:
+                  csEntry.symTypeString = "-nosymbols-";
+                  break;
+                  case SymCoff:
+                  csEntry.symTypeString = "COFF";
+                  break;
+                  case SymCv:
+                  csEntry.symTypeString = "CV";
+                  break;
+                  case SymPdb:
+                  csEntry.symTypeString = "PDB";
+                  break;
+                  case SymExport:
+                  csEntry.symTypeString = "-exported-";
+                  break;
+                  case SymDeferred:
+                  csEntry.symTypeString = "-deferred-";
+                  break;
+                  case SymSym:
+                  csEntry.symTypeString = "SYM";
+                  break;
+#if API_VERSION_NUMBER >= 9
+                  case SymDia:
+                  csEntry.symTypeString = "DIA";
+                  break;
+#endif
+                  case 8: //SymVirtual:
+                  csEntry.symTypeString = "Virtual";
+                  break;
+                  default:
+                  //_snprintf( ty, sizeof(ty), "symtype=%ld", (long) Module.SymType );
+                  csEntry.symTypeString = NULL;
+                  break;
+              }
+        
+              MyStrCpy(csEntry.moduleName, STACKWALK_MAX_NAMELEN, Module.ModuleName);
+              csEntry.baseOfImage = Module.BaseOfImage;
+              MyStrCpy(csEntry.loadedImageName, STACKWALK_MAX_NAMELEN, Module.LoadedImageName);
+          } // got module info OK
+          else
+          {
+              this->OnDbgHelpErr("SymGetModuleInfo64", GetLastError(), s.AddrPC.Offset);
+          }
+      }
+      else
+      {
+          MyStrCpy(csEntry.moduleName, STACKWALK_MAX_NAMELEN, "MODULE?");
+      }
+    } // we seem to have a valid PC
+
+    CallstackEntryType et = nextEntry;
+    if (frameNum == 0)
+      et = firstEntry;
+    bLastEntryCalled = false;
+    this->OnCallstackEntry(et, csEntry);
+    
+    if (s.AddrReturn.Offset == 0)
+    {
+      bLastEntryCalled = true;
+      this->OnCallstackEntry(lastEntry, csEntry);
+      SetLastError(ERROR_SUCCESS);
+      break;
+    }
+  } // for ( frameNum )
+
+  cleanup:
+    if (pSym) free( pSym );
+
+  if (bLastEntryCalled == false)
+      this->OnCallstackEntry(lastEntry, csEntry);
+
+  if (context == NULL)
+    ResumeThread(hThread);
+
+  return TRUE;
+}
+
+BOOL __stdcall StackWalker::myReadProcMem(
+    HANDLE      hProcess,
+    DWORD64     qwBaseAddress,
+    PVOID       lpBuffer,
+    DWORD       nSize,
+    LPDWORD     lpNumberOfBytesRead
+    )
+{
+  if (s_readMemoryFunction == NULL)
+  {
+    SIZE_T st;
+    BOOL bRet = ReadProcessMemory(hProcess, (LPVOID) qwBaseAddress, lpBuffer, nSize, &st);
+    *lpNumberOfBytesRead = (DWORD) st;
+    //printf("ReadMemory: hProcess: %p, baseAddr: %p, buffer: %p, size: %d, read: %d, result: %d\n", hProcess, (LPVOID) qwBaseAddress, lpBuffer, nSize, (DWORD) st, (DWORD) bRet);
+    return bRet;
+  }
+  else
+  {
+    return s_readMemoryFunction(hProcess, qwBaseAddress, lpBuffer, nSize, lpNumberOfBytesRead, s_readMemoryFunction_UserData);
+  }
+}
+
+void StackWalker::OnLoadModule(LPCSTR img, LPCSTR mod, DWORD64 baseAddr, DWORD size, DWORD result, LPCSTR symType, LPCSTR pdbName, ULONGLONG fileVersion)
+{
+  CHAR buffer[STACKWALK_MAX_NAMELEN];
+  if (fileVersion == 0)
+    _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "%s:%s (%p), size: %d (result: %d), SymType: '%s', PDB: '%s'\n", img, mod, (LPVOID) baseAddr, size, result, symType, pdbName);
+  else
+  {
+    DWORD v4 = (DWORD) (fileVersion & 0xFFFF);
+    DWORD v3 = (DWORD) ((fileVersion>>16) & 0xFFFF);
+    DWORD v2 = (DWORD) ((fileVersion>>32) & 0xFFFF);
+    DWORD v1 = (DWORD) ((fileVersion>>48) & 0xFFFF);
+    _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "%s:%s (%p), size: %d (result: %d), SymType: '%s', PDB: '%s', fileVersion: %d.%d.%d.%d\n", img, mod, (LPVOID) baseAddr, size, result, symType, pdbName, v1, v2, v3, v4);
+  }
+  if (m_verbose)
+  {
+      OnOutput(buffer);
+  }
+}
+
+void StackWalker::OnCallstackEntry(CallstackEntryType eType, CallstackEntry &entry)
+{
+  CHAR buffer[STACKWALK_MAX_NAMELEN];
+  if ( (eType != lastEntry) && (entry.offset != 0) )
+  {
+    if (entry.name[0] == 0)
+      MyStrCpy(entry.name, STACKWALK_MAX_NAMELEN, "(function-name not available)");
+    if (entry.undName[0] != 0)
+      MyStrCpy(entry.name, STACKWALK_MAX_NAMELEN, entry.undName);
+    if (entry.undFullName[0] != 0)
+      MyStrCpy(entry.name, STACKWALK_MAX_NAMELEN, entry.undFullName);
+    if (entry.lineFileName[0] == 0)
+    {
+      MyStrCpy(entry.lineFileName, STACKWALK_MAX_NAMELEN, "(filename not available)");
+      if (entry.moduleName[0] == 0)
+        MyStrCpy(entry.moduleName, STACKWALK_MAX_NAMELEN, "(module-name not available)");
+      _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "%p (%s): %s: %s\n", (LPVOID) entry.offset, entry.moduleName, entry.lineFileName, entry.name);
+    }
+    else
+      _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "%s (%d): %s\n", entry.lineFileName, entry.lineNumber, entry.name);
+    buffer[STACKWALK_MAX_NAMELEN-1] = 0;
+    OnOutput(buffer);
+  }
+}
+
+void StackWalker::OnDbgHelpErr(LPCSTR szFuncName, DWORD gle, DWORD64 addr)
+{
+  CHAR buffer[STACKWALK_MAX_NAMELEN];
+  _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "ERROR: %s, GetLastError: %d (Address: %p)\n", szFuncName, gle, (LPVOID) addr);
+  if (m_verbose)
+  {
+      OnOutput(buffer);
+  }
+}
+
+#pragma warning (disable : 4996)
+
+void StackWalker::OnSymInit(LPCSTR szSearchPath, DWORD symOptions, LPCSTR szUserName)
+{
+  CHAR buffer[STACKWALK_MAX_NAMELEN];
+  _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "SymInit: Symbol-SearchPath: '%s', symOptions: %d, UserName: '%s'\n", szSearchPath, symOptions, szUserName);
+  if (m_verbose)
+  {
+      OnOutput(buffer);
+  }
+  // Also display the OS-version
+#if _MSC_VER <= 1200
+  OSVERSIONINFOA ver;
+  ZeroMemory(&ver, sizeof(OSVERSIONINFOA));
+  ver.dwOSVersionInfoSize = sizeof(ver);
+  if (GetVersionExA(&ver) != FALSE)
+  {
+    _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "OS-Version: %d.%d.%d (%s)\n", 
+      ver.dwMajorVersion, ver.dwMinorVersion, ver.dwBuildNumber,
+      ver.szCSDVersion);
+    if (m_verbose)
+    {
+        OnOutput(buffer);
+    }
+  }
+#else
+  OSVERSIONINFOEXA ver;
+  ZeroMemory(&ver, sizeof(OSVERSIONINFOEXA));
+  ver.dwOSVersionInfoSize = sizeof(ver);
+  if (GetVersionExA( (OSVERSIONINFOA*) &ver) != FALSE)
+  {
+    _snprintf_s(buffer, STACKWALK_MAX_NAMELEN, "OS-Version: %d.%d.%d (%s) 0x%x-0x%x\n", 
+      ver.dwMajorVersion, ver.dwMinorVersion, ver.dwBuildNumber,
+      ver.szCSDVersion, ver.wSuiteMask, ver.wProductType);
+    if (m_verbose)
+    {
+        OnOutput(buffer);
+    }
+  }
+#endif
+}
+
+void StackWalker::OnOutput(LPCSTR buffer)
+{
+  OutputDebugStringA(buffer);
+}
+
+#endif // LL_WINDOWS
diff --git a/indra/llcommon/StackWalker.h b/indra/llcommon/StackWalker.h
new file mode 100644
index 0000000000..834f89c471
--- /dev/null
+++ b/indra/llcommon/StackWalker.h
@@ -0,0 +1,226 @@
+/**********************************************************************
+ * 
+ * StackWalker.h
+ *
+ *
+ *
+ * $LicenseInfo:firstyear=2016&license=bsd$
+ *
+ * Linden notes: Small modifications from the original source at https://stackwalker.codeplex.com/
+ *
+ * LICENSE (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ *   Copyright (c) 2005-2009, Jochen Kalmbach
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without modification, 
+ *   are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, 
+ *   this list of conditions and the following disclaimer. 
+ *   Redistributions in binary form must reproduce the above copyright notice, 
+ *   this list of conditions and the following disclaimer in the documentation 
+ *   and/or other materials provided with the distribution. 
+ *   Neither the name of Jochen Kalmbach nor the names of its contributors may be 
+ *   used to endorse or promote products derived from this software without 
+ *   specific prior written permission. 
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ *   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
+ *   THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ *   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
+ *   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
+ *   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+ *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 
+ *   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
+ *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * **********************************************************************/
+
+#if LL_WINDOWS
+
+// #pragma once is supported starting with _MCS_VER 1000, 
+// so we need not to check the version (because we only support _MSC_VER >= 1100)!
+#pragma once
+
+#include <windows.h>
+
+// special defines for VC5/6 (if no actual PSDK is installed):
+#if _MSC_VER < 1300
+typedef unsigned __int64 DWORD64, *PDWORD64;
+#if defined(_WIN64)
+typedef unsigned __int64 SIZE_T, *PSIZE_T;
+#else
+typedef unsigned long SIZE_T, *PSIZE_T;
+#endif
+#endif  // _MSC_VER < 1300
+
+class StackWalkerInternal;  // forward
+class StackWalker
+{
+public:
+  typedef enum StackWalkOptions
+  {
+    // No addition info will be retrived 
+    // (only the address is available)
+    RetrieveNone = 0,
+    
+    // Try to get the symbol-name
+    RetrieveSymbol = 1,
+    
+    // Try to get the line for this symbol
+    RetrieveLine = 2,
+    
+    // Try to retrieve the module-infos
+    RetrieveModuleInfo = 4,
+    
+    // Also retrieve the version for the DLL/EXE
+    RetrieveFileVersion = 8,
+    
+    // Contains all the abouve
+    RetrieveVerbose = 0xF,
+    
+    // Generate a "good" symbol-search-path
+    SymBuildPath = 0x10,
+    
+    // Also use the public Microsoft-Symbol-Server
+    SymUseSymSrv = 0x20,
+    
+    // Contains all the abouve "Sym"-options
+    SymAll = 0x30,
+    
+    // Contains all options (default)
+    OptionsAll = 0x3F
+  } StackWalkOptions;
+
+  StackWalker(
+    bool verbose = true,
+    int options = OptionsAll, // 'int' is by design, to combine the enum-flags
+    LPCSTR szSymPath = NULL, 
+    DWORD dwProcessId = GetCurrentProcessId(), 
+    HANDLE hProcess = GetCurrentProcess()
+    );
+  StackWalker(DWORD dwProcessId, HANDLE hProcess);
+  virtual ~StackWalker();
+
+  typedef BOOL (__stdcall *PReadProcessMemoryRoutine)(
+    HANDLE      hProcess,
+    DWORD64     qwBaseAddress,
+    PVOID       lpBuffer,
+    DWORD       nSize,
+    LPDWORD     lpNumberOfBytesRead,
+    LPVOID      pUserData  // optional data, which was passed in "ShowCallstack"
+    );
+
+  BOOL LoadModules();
+
+  BOOL ShowCallstack(
+    bool verbose,
+    HANDLE hThread = GetCurrentThread(), 
+    const CONTEXT *context = NULL, 
+    PReadProcessMemoryRoutine readMemoryFunction = NULL,
+    LPVOID pUserData = NULL  // optional to identify some data in the 'readMemoryFunction'-callback
+    );
+
+#if _MSC_VER >= 1300
+// due to some reasons, the "STACKWALK_MAX_NAMELEN" must be declared as "public" 
+// in older compilers in order to use it... starting with VC7 we can declare it as "protected"
+protected:
+#endif
+	enum { STACKWALK_MAX_NAMELEN = 4096 }; // max name length for found symbols
+
+protected:
+  // Entry for each Callstack-Entry
+  typedef struct CallstackEntry
+  {
+    DWORD64 offset;  // if 0, we have no valid entry
+    CHAR name[STACKWALK_MAX_NAMELEN];
+    CHAR undName[STACKWALK_MAX_NAMELEN];
+    CHAR undFullName[STACKWALK_MAX_NAMELEN];
+    DWORD64 offsetFromSmybol;
+    DWORD offsetFromLine;
+    DWORD lineNumber;
+    CHAR lineFileName[STACKWALK_MAX_NAMELEN];
+    DWORD symType;
+    LPCSTR symTypeString;
+    CHAR moduleName[STACKWALK_MAX_NAMELEN];
+    DWORD64 baseOfImage;
+    CHAR loadedImageName[STACKWALK_MAX_NAMELEN];
+  } CallstackEntry;
+
+  typedef enum CallstackEntryType {firstEntry, nextEntry, lastEntry};
+
+  virtual void OnSymInit(LPCSTR szSearchPath, DWORD symOptions, LPCSTR szUserName);
+  virtual void OnLoadModule(LPCSTR img, LPCSTR mod, DWORD64 baseAddr, DWORD size, DWORD result, LPCSTR symType, LPCSTR pdbName, ULONGLONG fileVersion);
+  virtual void OnCallstackEntry(CallstackEntryType eType, CallstackEntry &entry);
+  virtual void OnDbgHelpErr(LPCSTR szFuncName, DWORD gle, DWORD64 addr);
+  virtual void OnOutput(LPCSTR szText);
+
+  StackWalkerInternal *m_sw;
+  HANDLE m_hProcess;
+  DWORD m_dwProcessId;
+  BOOL m_modulesLoaded;
+  LPSTR m_szSymPath;
+
+  bool m_verbose;
+  int m_options;
+  int m_MaxRecursionCount;
+
+  static BOOL __stdcall myReadProcMem(HANDLE hProcess, DWORD64 qwBaseAddress, PVOID lpBuffer, DWORD nSize, LPDWORD lpNumberOfBytesRead);
+
+  friend StackWalkerInternal;
+};  // class StackWalker
+
+
+// The "ugly" assembler-implementation is needed for systems before XP
+// If you have a new PSDK and you only compile for XP and later, then you can use 
+// the "RtlCaptureContext"
+// Currently there is no define which determines the PSDK-Version... 
+// So we just use the compiler-version (and assumes that the PSDK is 
+// the one which was installed by the VS-IDE)
+
+// INFO: If you want, you can use the RtlCaptureContext if you only target XP and later...
+//       But I currently use it in x64/IA64 environments...
+//#if defined(_M_IX86) && (_WIN32_WINNT <= 0x0500) && (_MSC_VER < 1400)
+
+#if defined(_M_IX86)
+#ifdef CURRENT_THREAD_VIA_EXCEPTION
+// TODO: The following is not a "good" implementation, 
+// because the callstack is only valid in the "__except" block...
+#define GET_CURRENT_CONTEXT_STACKWALKER_CODEPLEX(c, contextFlags) \
+  do { \
+    memset(&c, 0, sizeof(CONTEXT)); \
+    EXCEPTION_POINTERS *pExp = NULL; \
+    __try { \
+      throw 0; \
+    } __except( ( (pExp = GetExceptionInformation()) ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_EXECUTE_HANDLER)) {} \
+    if (pExp != NULL) \
+      memcpy(&c, pExp->ContextRecord, sizeof(CONTEXT)); \
+      c.ContextFlags = contextFlags; \
+  } while(0);
+#else
+// The following should be enough for walking the callstack...
+#define GET_CURRENT_CONTEXT_STACKWALKER_CODEPLEX(c, contextFlags) \
+  do { \
+    memset(&c, 0, sizeof(CONTEXT)); \
+    c.ContextFlags = contextFlags; \
+    __asm    call x \
+    __asm x: pop eax \
+    __asm    mov c.Eip, eax \
+    __asm    mov c.Ebp, ebp \
+    __asm    mov c.Esp, esp \
+  } while(0);
+#endif
+
+#else
+
+// The following is defined for x86 (XP and higher), x64 and IA64:
+#define GET_CURRENT_CONTEXT_STACKWALKER_CODEPLEX(c, contextFlags) \
+  do { \
+    memset(&c, 0, sizeof(CONTEXT)); \
+    c.ContextFlags = contextFlags; \
+    RtlCaptureContext(&c); \
+} while(0);
+#endif
+
+#endif // LL_WINDOWS
diff --git a/indra/llcommon/llallocator.cpp b/indra/llcommon/llallocator.cpp
index 34fc28d8cc..ac97fb71dd 100644
--- a/indra/llcommon/llallocator.cpp
+++ b/indra/llcommon/llallocator.cpp
@@ -27,47 +27,6 @@
 #include "linden_common.h"
 #include "llallocator.h"
 
-#if (LL_USE_TCMALLOC && LL_USE_HEAP_PROFILER)
-
-#include "google/heap-profiler.h"
-#include "google/commandlineflags_public.h"
-
-DECLARE_bool(heap_profile_use_stack_trace);
-//DECLARE_double(tcmalloc_release_rate);
-
-void LLAllocator::setProfilingEnabled(bool should_enable)
-{
-    // NULL disables dumping to disk
-    static char const * const PREFIX = NULL;
-    if(should_enable)
-    {
-		HeapProfilerSetUseStackTrace(false);
-        HeapProfilerStart(PREFIX);
-    }
-    else
-    {
-        HeapProfilerStop();
-    }
-}
-
-// static
-bool LLAllocator::isProfiling()
-{
-    return IsHeapProfilerRunning();
-}
-
-std::string LLAllocator::getRawProfile()
-{
-    // *TODO - fix google-perftools to accept an buffer to avoid this
-    // malloc-copy-free cycle.
-    char * buffer = GetHeapProfile();
-    std::string ret = buffer;
-    free(buffer);
-    return ret;
-}
-
-#else // LL_USE_TCMALLOC
-
 //
 // stub implementations for when tcmalloc is disabled
 //
@@ -87,8 +46,6 @@ std::string LLAllocator::getRawProfile()
     return std::string();
 }
 
-#endif // LL_USE_TCMALLOC
-
 LLAllocatorHeapProfile const & LLAllocator::getProfile()
 {
     mProf.mLines.clear();
diff --git a/indra/llcommon/llapp.cpp b/indra/llcommon/llapp.cpp
index eb0699ad41..2c76f29020 100644
--- a/indra/llcommon/llapp.cpp
+++ b/indra/llcommon/llapp.cpp
@@ -48,6 +48,7 @@
 #include "lleventtimer.h"
 #include "google_breakpad/exception_handler.h"
 #include "stringize.h"
+#include "llcleanup.h"
 
 //
 // Signal handling
@@ -177,7 +178,7 @@ LLApp::~LLApp()
 	
 	if(mExceptionHandler != 0) delete mExceptionHandler;
 
-	LLCommon::cleanupClass();
+	SUBSYSTEM_CLEANUP(LLCommon);
 }
 
 // static
diff --git a/indra/llcommon/llapp.h b/indra/llcommon/llapp.h
index d9933b3d36..ff9a92b45f 100644
--- a/indra/llcommon/llapp.h
+++ b/indra/llcommon/llapp.h
@@ -172,12 +172,12 @@ public:
 	virtual bool cleanup() = 0;			// Override to do application cleanup
 
 	//
-	// mainLoop()
+	// frame()
 	//
-	// Runs the application main loop.  It's assumed that when you exit
-	// this method, the application is in one of the cleanup states, either QUITTING or ERROR
+	// Pass control to the application for a single frame. Returns 'done'
+	// flag: if frame() returns false, it expects to be called again.
 	//
-	virtual bool mainLoop() = 0; // Override for the application main loop.  Needs to at least gracefully notice the QUITTING state and exit.
+	virtual bool frame() = 0; // Override for application body logic
 
 	//
 	// Crash logging
diff --git a/indra/llcommon/llapr.cpp b/indra/llcommon/llapr.cpp
index a548c96002..86f407cdb0 100644
--- a/indra/llcommon/llapr.cpp
+++ b/indra/llcommon/llapr.cpp
@@ -294,9 +294,11 @@ void LLScopedLock::unlock()
 bool ll_apr_warn_status(apr_status_t status)
 {
 	if(APR_SUCCESS == status) return false;
+#if !LL_LINUX
 	char buf[MAX_STRING];	/* Flawfinder: ignore */
 	apr_strerror(status, buf, sizeof(buf));
 	LL_WARNS("APR") << "APR: " << buf << LL_ENDL;
+#endif
 	return true;
 }
 
diff --git a/indra/llcommon/llassettype.cpp b/indra/llcommon/llassettype.cpp
index 5ae2df3994..4304db36be 100644
--- a/indra/llcommon/llassettype.cpp
+++ b/indra/llcommon/llassettype.cpp
@@ -63,8 +63,7 @@ struct AssetEntry : public LLDictionaryEntry
 class LLAssetDictionary : public LLSingleton<LLAssetDictionary>,
 						  public LLDictionary<LLAssetType::EType, AssetEntry>
 {
-public:
-	LLAssetDictionary();
+	LLSINGLETON(LLAssetDictionary);
 };
 
 LLAssetDictionary::LLAssetDictionary()
diff --git a/indra/llcommon/llcallstack.cpp b/indra/llcommon/llcallstack.cpp
new file mode 100644
index 0000000000..8db291eed1
--- /dev/null
+++ b/indra/llcommon/llcallstack.cpp
@@ -0,0 +1,190 @@
+/** 
+ * @file llcallstack.cpp
+ * @brief run-time extraction of the current callstack
+ *
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2016, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+
+#include "llcommon.h"
+#include "llcallstack.h"
+#include "StackWalker.h"
+#include "llthreadlocalstorage.h"
+
+#if LL_WINDOWS
+class LLCallStackImpl: public StackWalker
+{
+public:
+    LLCallStackImpl():
+        StackWalker(false,0) // non-verbose, options = 0
+    {
+    }
+    ~LLCallStackImpl()
+    {
+    }
+    void getStack(std::vector<std::string>& stack, S32 skip_count=0, bool verbose=false)
+    {
+        m_stack.clear();
+        ShowCallstack(verbose);
+        // Skip the first few lines because they're just bookkeeping for LLCallStack,
+        // plus any additional lines requested to skip.
+        S32 first_line = skip_count + 3;
+        for (S32 i=first_line; i<m_stack.size(); ++i)
+        {
+            stack.push_back(m_stack[i]);
+        }
+    }
+protected:
+    virtual void OnOutput(LPCSTR szText)
+    {
+        m_stack.push_back(szText);
+    }
+    std::vector<std::string> m_stack;
+};
+#else
+// Stub - not implemented currently on other platforms.
+class LLCallStackImpl
+{
+public:
+    LLCallStackImpl() {}
+    ~LLCallStackImpl() {}
+    void getStack(std::vector<std::string>& stack, S32 skip_count=0, bool verbose=false)
+    {
+        stack.clear();
+    }
+};
+#endif
+
+LLCallStackImpl *LLCallStack::s_impl = NULL;
+
+LLCallStack::LLCallStack(S32 skip_count, bool verbose):
+    m_skipCount(skip_count),
+    m_verbose(verbose)
+{
+    if (!s_impl)
+    {
+        s_impl = new LLCallStackImpl;
+    }
+    LLTimer t;
+    s_impl->getStack(m_strings, m_skipCount, m_verbose);
+}
+
+bool LLCallStack::contains(const std::string& str)
+{
+    for (std::vector<std::string>::const_iterator it = m_strings.begin();
+         it != m_strings.end(); ++it)
+    {
+        if (it->find(str) != std::string::npos)
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+std::ostream& operator<<(std::ostream& s, const LLCallStack& call_stack)
+{
+#ifndef LL_RELEASE_FOR_DOWNLOAD
+    std::vector<std::string>::const_iterator it;
+    for (it=call_stack.m_strings.begin(); it!=call_stack.m_strings.end(); ++it)
+    {
+        s << *it;
+    }
+#else
+    s << "UNAVAILABLE IN RELEASE";
+#endif
+    return s;
+}
+
+LLContextStrings::LLContextStrings()
+{
+}
+
+// static
+LLContextStrings* LLContextStrings::getThreadLocalInstance()
+{
+	LLContextStrings *cons = LLThreadLocalSingletonPointer<LLContextStrings>::getInstance();
+    if (!cons)
+    {
+        LLThreadLocalSingletonPointer<LLContextStrings>::setInstance(new LLContextStrings);
+    }
+	return LLThreadLocalSingletonPointer<LLContextStrings>::getInstance();
+}
+
+// static
+void LLContextStrings::addContextString(const std::string& str)
+{
+	LLContextStrings *cons = getThreadLocalInstance();
+    //LL_INFOS() << "CTX " << (S32)cons << " ADD " << str << " CNT " << cons->m_contextStrings[str] << LL_ENDL;
+	cons->m_contextStrings[str]++;
+}
+
+// static
+void LLContextStrings::removeContextString(const std::string& str)
+{
+	LLContextStrings *cons = getThreadLocalInstance();
+	cons->m_contextStrings[str]--;
+    //LL_INFOS() << "CTX " << (S32)cons << " REMOVE " << str << " CNT " << cons->m_contextStrings[str] << LL_ENDL;
+    if (cons->m_contextStrings[str] == 0)
+    {
+        cons->m_contextStrings.erase(str);
+    }
+}
+
+// static
+bool LLContextStrings::contains(const std::string& str)
+{
+    const std::map<std::string,S32>& strings =
+        LLThreadLocalSingletonPointer<LLContextStrings>::getInstance()->m_contextStrings;
+    for (std::map<std::string,S32>::const_iterator it = strings.begin(); it!=strings.end(); ++it)
+    {
+        if (it->first.find(str) != std::string::npos)
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+// static
+void LLContextStrings::output(std::ostream& os)
+{
+    const std::map<std::string,S32>& strings =
+        LLThreadLocalSingletonPointer<LLContextStrings>::getInstance()->m_contextStrings;
+    for (std::map<std::string,S32>::const_iterator it = strings.begin(); it!=strings.end(); ++it)
+    {
+        os << it->first << "[" << it->second << "]" << "\n";
+    }
+}
+
+// static 
+std::ostream& operator<<(std::ostream& s, const LLContextStatus& context_status)
+{
+    LLThreadLocalSingletonPointer<LLContextStrings>::getInstance()->output(s);
+    return s;
+}
+
+bool LLContextStatus::contains(const std::string& str)
+{
+    return LLThreadLocalSingletonPointer<LLContextStrings>::getInstance()->contains(str);
+}
diff --git a/indra/llcommon/llcallstack.h b/indra/llcommon/llcallstack.h
new file mode 100644
index 0000000000..1f7a7689d7
--- /dev/null
+++ b/indra/llcommon/llcallstack.h
@@ -0,0 +1,80 @@
+/** 
+ * @file llcallstack.h
+ * @brief run-time extraction of the current callstack
+ *
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2016, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include <map>
+
+class LLCallStackImpl;
+
+class LLCallStack
+{
+public:
+    LLCallStack(S32 skip_count=0, bool verbose=false);
+    std::vector<std::string> m_strings;
+    bool m_verbose;
+    bool contains(const std::string& str);
+private:
+    static LLCallStackImpl *s_impl;
+    S32 m_skipCount;
+};
+
+LL_COMMON_API std::ostream& operator<<(std::ostream& s, const LLCallStack& call_stack);
+
+class LLContextStrings
+{
+public:
+    LLContextStrings();
+    static void addContextString(const std::string& str);
+    static void removeContextString(const std::string& str);
+    static void output(std::ostream& os);
+    static LLContextStrings* getThreadLocalInstance();
+    static bool contains(const std::string& str);
+private:
+    std::map<std::string,S32> m_contextStrings;
+};
+
+class LLScopedContextString
+{
+public:
+    LLScopedContextString(const std::string& str):
+        m_str(str)
+    {
+        LLContextStrings::addContextString(m_str);
+    }
+    ~LLScopedContextString()
+    {
+        LLContextStrings::removeContextString(m_str);
+    }
+private:
+    std::string m_str;
+};
+
+// Mostly exists as a class to hook an ostream override to.
+struct LLContextStatus
+{
+    bool contains(const std::string& str);
+};
+
+LL_COMMON_API std::ostream& operator<<(std::ostream& s, const LLContextStatus& context_status);
diff --git a/indra/llcommon/llcleanup.cpp b/indra/llcommon/llcleanup.cpp
new file mode 100644
index 0000000000..c5283507bf
--- /dev/null
+++ b/indra/llcommon/llcleanup.cpp
@@ -0,0 +1,29 @@
+/**
+ * @file   llcleanup.cpp
+ * @author Nat Goodspeed
+ * @date   2016-08-30
+ * @brief  Implementation for llcleanup.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llcleanup.h"
+// STL headers
+// std headers
+// external library headers
+// other Linden headers
+#include "llerror.h"
+#include "llerrorcontrol.h"
+
+void log_subsystem_cleanup(const char* file, int line, const char* function,
+                           const char* classname)
+{
+    LL_INFOS("Cleanup") << LLError::abbreviateFile(file) << "(" << line << "): "
+                        << "calling " << classname << "::cleanupClass() in "
+                        << function << LL_ENDL;
+}
diff --git a/indra/llcommon/llcleanup.h b/indra/llcommon/llcleanup.h
new file mode 100644
index 0000000000..a319171b5f
--- /dev/null
+++ b/indra/llcommon/llcleanup.h
@@ -0,0 +1,33 @@
+/**
+ * @file   llcleanup.h
+ * @author Nat Goodspeed
+ * @date   2015-05-20
+ * @brief  Mechanism for cleaning up subsystem resources
+ * 
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLCLEANUP_H)
+#define LL_LLCLEANUP_H
+
+#include <boost/current_function.hpp>
+
+// Instead of directly calling SomeClass::cleanupClass(), use
+// SUBSYSTEM_CLEANUP(SomeClass);
+// This logs the call as well as performing it. That gives us a baseline
+// subsystem shutdown order against which to compare subsequent dynamic
+// shutdown schemes.
+#define SUBSYSTEM_CLEANUP(CLASSNAME)                                    \
+    do {                                                                \
+        log_subsystem_cleanup(__FILE__, __LINE__, BOOST_CURRENT_FUNCTION, #CLASSNAME); \
+        CLASSNAME::cleanupClass();                                      \
+    } while (0)
+// Use ancient do { ... } while (0) macro trick to permit a block of
+// statements with the same syntax as a single statement.
+
+void log_subsystem_cleanup(const char* file, int line, const char* function,
+                           const char* classname);
+
+#endif /* ! defined(LL_LLCLEANUP_H) */
diff --git a/indra/llcommon/llcommon.cpp b/indra/llcommon/llcommon.cpp
index 19642b0982..439ff4e628 100644
--- a/indra/llcommon/llcommon.cpp
+++ b/indra/llcommon/llcommon.cpp
@@ -31,6 +31,7 @@
 #include "llthread.h"
 #include "lltrace.h"
 #include "lltracethreadrecorder.h"
+#include "llcleanup.h"
 
 //static
 BOOL LLCommon::sAprInitialized = FALSE;
@@ -63,11 +64,11 @@ void LLCommon::cleanupClass()
 	sMasterThreadRecorder = NULL;
 	LLTrace::set_master_thread_recorder(NULL);
 	LLThreadSafeRefCount::cleanupThreadSafeRefCount();
-	LLTimer::cleanupClass();
+	SUBSYSTEM_CLEANUP(LLTimer);
 	if (sAprInitialized)
 	{
 		ll_cleanup_apr();
 		sAprInitialized = FALSE;
 	}
-	LLMemory::cleanupClass();
+	SUBSYSTEM_CLEANUP(LLMemory);
 }
diff --git a/indra/llcommon/llcoro_get_id.cpp b/indra/llcommon/llcoro_get_id.cpp
new file mode 100644
index 0000000000..24ed1fe0c9
--- /dev/null
+++ b/indra/llcommon/llcoro_get_id.cpp
@@ -0,0 +1,32 @@
+/**
+ * @file   llcoro_get_id.cpp
+ * @author Nat Goodspeed
+ * @date   2016-09-03
+ * @brief  Implementation for llcoro_get_id.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llcoro_get_id.h"
+// STL headers
+// std headers
+// external library headers
+// other Linden headers
+#include "llcoros.h"
+
+namespace llcoro
+{
+
+id get_id()
+{
+    // An instance of Current can convert to LLCoros::CoroData*, which can
+    // implicitly convert to void*, which is an llcoro::id.
+    return LLCoros::Current();
+}
+
+} // llcoro
diff --git a/indra/llcommon/llcoro_get_id.h b/indra/llcommon/llcoro_get_id.h
new file mode 100644
index 0000000000..4c1dca6f19
--- /dev/null
+++ b/indra/llcommon/llcoro_get_id.h
@@ -0,0 +1,30 @@
+/**
+ * @file   llcoro_get_id.h
+ * @author Nat Goodspeed
+ * @date   2016-09-03
+ * @brief  Supplement the functionality in llcoro.h.
+ *
+ *         This is broken out as a separate header file to resolve
+ *         circularity: LLCoros isa LLSingleton, yet LLSingleton machinery
+ *         requires llcoro::get_id().
+ *
+ *         Be very suspicious of anyone else #including this header.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLCORO_GET_ID_H)
+#define LL_LLCORO_GET_ID_H
+
+namespace llcoro
+{
+
+/// Get an opaque, distinct token for the running coroutine (or main).
+typedef void* id;
+id get_id();
+
+} // llcoro
+
+#endif /* ! defined(LL_LLCORO_GET_ID_H) */
diff --git a/indra/llcommon/llcoros.cpp b/indra/llcommon/llcoros.cpp
index d16bf0160b..1e1dfd2602 100644
--- a/indra/llcommon/llcoros.cpp
+++ b/indra/llcommon/llcoros.cpp
@@ -38,33 +38,81 @@
 #include "llevents.h"
 #include "llerror.h"
 #include "stringize.h"
+#include "llexception.h"
 
-// do nothing, when we need nothing done
+namespace {
+void no_op() {}
+} // anonymous namespace
+
+// Do nothing, when we need nothing done. This is a static member of LLCoros
+// because CoroData is a private nested class.
 void LLCoros::no_cleanup(CoroData*) {}
 
 // CoroData for the currently-running coroutine. Use a thread_specific_ptr
 // because each thread potentially has its own distinct pool of coroutines.
-// This thread_specific_ptr does NOT own the CoroData object! That's owned by
-// LLCoros::mCoros. It merely identifies it. For this reason we instantiate
-// it with a no-op cleanup function.
-boost::thread_specific_ptr<LLCoros::CoroData>
-LLCoros::sCurrentCoro(LLCoros::no_cleanup);
+LLCoros::Current::Current()
+{
+    // Use a function-static instance so this thread_specific_ptr is
+    // instantiated on demand. Since we happen to know it's consumed by
+    // LLSingleton, this is likely to happen before the runtime has finished
+    // initializing module-static data. For the same reason, we can't package
+    // this pointer in an LLSingleton.
+
+    // This thread_specific_ptr does NOT own the CoroData object! That's owned
+    // by LLCoros::mCoros. It merely identifies it. For this reason we
+    // instantiate it with a no-op cleanup function.
+    static boost::thread_specific_ptr<LLCoros::CoroData> sCurrent(LLCoros::no_cleanup);
+
+    // If this is the first time we're accessing sCurrent for the running
+    // thread, its get() will be NULL. This could be a problem, in that
+    // llcoro::get_id() would return the same (NULL) token value for the "main
+    // coroutine" in every thread, whereas what we really want is a distinct
+    // value for every distinct stack in the process. So if get() is NULL,
+    // give it a heap CoroData: this ensures that llcoro::get_id() will return
+    // distinct values.
+    // This tactic is "leaky": sCurrent explicitly does not destroy any
+    // CoroData to which it points, and we do NOT enter these "main coroutine"
+    // CoroData instances in the LLCoros::mCoros map. They are dummy entries,
+    // and they will leak at process shutdown: one CoroData per thread.
+    if (! sCurrent.get())
+    {
+        // It's tempting to provide a distinct name for each thread's "main
+        // coroutine." But as getName() has always returned the empty string
+        // to mean "not in a coroutine," empty string should suffice here --
+        // and truthfully the additional (thread-safe!) machinery to ensure
+        // uniqueness just doesn't feel worth the trouble.
+        // We use a no-op callable and a minimal stack size because, although
+        // CoroData's constructor in fact initializes its mCoro with a
+        // coroutine with that stack size, no one ever actually enters it by
+        // calling mCoro().
+        sCurrent.reset(new CoroData(0,  // no prev
+                                    "", // not a named coroutine
+                                    no_op,  // no-op callable
+                                    1024)); // stacksize moot
+    }
+
+    mCurrent = &sCurrent;
+}
 
 //static
 LLCoros::CoroData& LLCoros::get_CoroData(const std::string& caller)
 {
-    CoroData* current = sCurrentCoro.get();
-    if (! current)
-    {
-        LL_ERRS("LLCoros") << "Calling " << caller << " from non-coroutine context!" << LL_ENDL;
-    }
+    CoroData* current = Current();
+    // With the dummy CoroData set in LLCoros::Current::Current(), this
+    // pointer should never be NULL.
+    llassert_always(current);
     return *current;
 }
 
 //static
 LLCoros::coro::self& LLCoros::get_self()
 {
-    return *get_CoroData("get_self()").mSelf;
+    CoroData& current = get_CoroData("get_self()");
+    if (! current.mSelf)
+    {
+        LL_ERRS("LLCoros") << "Calling get_self() from non-coroutine context!" << LL_ENDL;
+    }
+    return *current.mSelf;
 }
 
 //static
@@ -79,20 +127,23 @@ bool LLCoros::get_consuming()
     return get_CoroData("get_consuming()").mConsuming;
 }
 
-llcoro::Suspending::Suspending():
-    mSuspended(LLCoros::sCurrentCoro.get())
+llcoro::Suspending::Suspending()
 {
-    // Revert mCurrentCoro to the value it had at the moment we last switched
+    LLCoros::Current current;
+    // Remember currently-running coroutine: we're about to suspend it.
+    mSuspended = current;
+    // Revert Current to the value it had at the moment we last switched
     // into this coroutine.
-    LLCoros::sCurrentCoro.reset(mSuspended->mPrev);
+    current.reset(mSuspended->mPrev);
 }
 
 llcoro::Suspending::~Suspending()
 {
+    LLCoros::Current current;
     // Okay, we're back, update our mPrev
-    mSuspended->mPrev = LLCoros::sCurrentCoro.get();
-    // and reinstate our sCurrentCoro.
-    LLCoros::sCurrentCoro.reset(mSuspended);
+    mSuspended->mPrev = current;
+    // and reinstate our Current.
+    current.reset(mSuspended);
 }
 
 LLCoros::LLCoros():
@@ -100,7 +151,11 @@ LLCoros::LLCoros():
     // Previously we used
     // boost::context::guarded_stack_allocator::default_stacksize();
     // empirically this is 64KB on Windows and Linux. Try quadrupling.
+#if ADDRESS_SIZE == 64
+    mStackSize(512*1024)
+#else
     mStackSize(256*1024)
+#endif
 {
     // Register our cleanup() method for "mainloop" ticks
     LLEventPumps::instance().obtain("mainloop").listen(
@@ -131,9 +186,9 @@ bool LLCoros::cleanup(const LLSD&)
             if ((previousCount < 5) || !(previousCount % 50))
             {
                 if (previousCount < 5)
-                    LL_INFOS("LLCoros") << "LLCoros: cleaning up coroutine " << mi->first << LL_ENDL;
+                    LL_DEBUGS("LLCoros") << "LLCoros: cleaning up coroutine " << mi->first << LL_ENDL;
                 else
-                    LL_INFOS("LLCoros") << "LLCoros: cleaning up coroutine " << mi->first << "("<< previousCount << ")" << LL_ENDL;
+                    LL_DEBUGS("LLCoros") << "LLCoros: cleaning up coroutine " << mi->first << "("<< previousCount << ")" << LL_ENDL;
 
             }
             // The erase() call will invalidate its passed iterator value --
@@ -185,9 +240,9 @@ std::string LLCoros::generateDistinctName(const std::string& prefix) const
             if ((previousCount < 5) || !(previousCount % 50))
             {
                 if (previousCount < 5)
-                    LL_INFOS("LLCoros") << "LLCoros: launching coroutine " << name << LL_ENDL;
+                    LL_DEBUGS("LLCoros") << "LLCoros: launching coroutine " << name << LL_ENDL;
                 else
-                    LL_INFOS("LLCoros") << "LLCoros: launching coroutine " << name << "(" << previousCount << ")" << LL_ENDL;
+                    LL_DEBUGS("LLCoros") << "LLCoros: launching coroutine " << name << "(" << previousCount << ")" << LL_ENDL;
 
             }
 
@@ -212,33 +267,43 @@ bool LLCoros::kill(const std::string& name)
 
 std::string LLCoros::getName() const
 {
-    CoroData* current = sCurrentCoro.get();
-    if (! current)
-    {
-        // not in a coroutine
-        return "";
-    }
-    return current->mName;
+    return Current()->mName;
 }
 
 void LLCoros::setStackSize(S32 stacksize)
 {
-    LL_INFOS("LLCoros") << "Setting coroutine stack size to " << stacksize << LL_ENDL;
+    LL_DEBUGS("LLCoros") << "Setting coroutine stack size to " << stacksize << LL_ENDL;
     mStackSize = stacksize;
 }
 
 // Top-level wrapper around caller's coroutine callable. This function accepts
-// the coroutine library's implicit coro::self& parameter and sets sCurrentSelf
-// but does not pass it down to the caller's callable.
+// the coroutine library's implicit coro::self& parameter and saves it, but
+// does not pass it down to the caller's callable.
 void LLCoros::toplevel(coro::self& self, CoroData* data, const callable_t& callable)
 {
     // capture the 'self' param in CoroData
     data->mSelf = &self;
     // run the code the caller actually wants in the coroutine
-    callable();
+    try
+    {
+        callable();
+    }
+    catch (const LLContinueError&)
+    {
+        // Any uncaught exception derived from LLContinueError will be caught
+        // here and logged. This coroutine will terminate but the rest of the
+        // viewer will carry on.
+        LOG_UNHANDLED_EXCEPTION(STRINGIZE("coroutine " << data->mName));
+    }
+    catch (...)
+    {
+        // Any OTHER kind of uncaught exception will cause the viewer to
+        // crash, hopefully informatively.
+        CRASH_ON_UNHANDLED_EXCEPTION(STRINGIZE("coroutine " << data->mName));
+    }
     // This cleanup isn't perfectly symmetrical with the way we initially set
-    // data->mPrev, but this is our last chance to reset mCurrentCoro.
-    sCurrentCoro.reset(data->mPrev);
+    // data->mPrev, but this is our last chance to reset Current.
+    Current().reset(data->mPrev);
 }
 
 /*****************************************************************************
@@ -261,7 +326,7 @@ LLCoros::CoroData::CoroData(CoroData* prev, const std::string& name,
     mPrev(prev),
     mName(name),
     // Wrap the caller's callable in our toplevel() function so we can manage
-    // sCurrentCoro appropriately at startup and shutdown of each coroutine.
+    // Current appropriately at startup and shutdown of each coroutine.
     mCoro(boost::bind(toplevel, _1, this, callable), stacksize),
     // don't consume events unless specifically directed
     mConsuming(false),
@@ -272,13 +337,13 @@ LLCoros::CoroData::CoroData(CoroData* prev, const std::string& name,
 std::string LLCoros::launch(const std::string& prefix, const callable_t& callable)
 {
     std::string name(generateDistinctName(prefix));
-    // pass the current value of sCurrentCoro as previous context
-    CoroData* newCoro = new CoroData(sCurrentCoro.get(), name,
-                                     callable, mStackSize);
+    Current current;
+    // pass the current value of Current as previous context
+    CoroData* newCoro = new CoroData(current, name, callable, mStackSize);
     // Store it in our pointer map
     mCoros.insert(name, newCoro);
     // also set it as current
-    sCurrentCoro.reset(newCoro);
+    current.reset(newCoro);
     /* Run the coroutine until its first wait, then return here */
     (newCoro->mCoro)(std::nothrow);
     return name;
diff --git a/indra/llcommon/llcoros.h b/indra/llcommon/llcoros.h
index 39316ed0e6..bbe2d22af4 100644
--- a/indra/llcommon/llcoros.h
+++ b/indra/llcommon/llcoros.h
@@ -35,8 +35,10 @@
 #include <boost/ptr_container/ptr_map.hpp>
 #include <boost/function.hpp>
 #include <boost/thread/tss.hpp>
+#include <boost/noncopyable.hpp>
 #include <string>
 #include <stdexcept>
+#include "llcoro_get_id.h"          // for friend declaration
 
 // forward-declare helper class
 namespace llcoro
@@ -83,6 +85,7 @@ class Suspending;
  */
 class LL_COMMON_API LLCoros: public LLSingleton<LLCoros>
 {
+    LLSINGLETON(LLCoros);
 public:
     /// Canonical boost::dcoroutines::coroutine signature we use
     typedef boost::dcoroutines::coroutine<void()> coro;
@@ -173,9 +176,8 @@ public:
     class Future;
 
 private:
-    LLCoros();
-    friend class LLSingleton<LLCoros>;
     friend class llcoro::Suspending;
+    friend llcoro::id llcoro::get_id();
     std::string generateDistinctName(const std::string& prefix) const;
     bool cleanup(const LLSD&);
     struct CoroData;
@@ -222,8 +224,22 @@ private:
     typedef boost::ptr_map<std::string, CoroData> CoroMap;
     CoroMap mCoros;
 
-    // identify the current coroutine's CoroData
-    static boost::thread_specific_ptr<LLCoros::CoroData> sCurrentCoro;
+    // Identify the current coroutine's CoroData. Use a little helper class so
+    // a caller can either use a temporary instance, or instantiate a named
+    // variable and access it multiple times.
+    class Current
+    {
+    public:
+        Current();
+
+        operator LLCoros::CoroData*() { return get(); }
+        LLCoros::CoroData* operator->() { return get(); }
+        LLCoros::CoroData* get() { return mCurrent->get(); }
+        void reset(LLCoros::CoroData* ptr) { mCurrent->reset(ptr); }
+
+    private:
+        boost::thread_specific_ptr<LLCoros::CoroData>* mCurrent;
+    };
 };
 
 namespace llcoro
@@ -231,7 +247,7 @@ namespace llcoro
 
 /// Instantiate one of these in a block surrounding any leaf point when
 /// control literally switches away from this coroutine.
-class Suspending
+class Suspending: boost::noncopyable
 {
 public:
     Suspending();
diff --git a/indra/llcommon/lldependencies.cpp b/indra/llcommon/lldependencies.cpp
index 0e72c175cb..0d5757effd 100644
--- a/indra/llcommon/lldependencies.cpp
+++ b/indra/llcommon/lldependencies.cpp
@@ -40,6 +40,7 @@
 #include <boost/graph/topological_sort.hpp>
 #include <boost/graph/exception.hpp>
 // other Linden headers
+#include "llexception.h"
 
 LLDependenciesBase::VertexList LLDependenciesBase::topo_sort(int vertices, const EdgeList& edges) const
 {
@@ -76,7 +77,7 @@ LLDependenciesBase::VertexList LLDependenciesBase::topo_sort(int vertices, const
         // Omit independent nodes: display only those that might contribute to
         // the cycle.
         describe(out, false);
-        throw Cycle(out.str());
+        LLTHROW(Cycle(out.str()));
     }
     // A peculiarity of boost::topological_sort() is that it emits results in
     // REVERSE topological order: to get the result you want, you must
diff --git a/indra/llcommon/lldependencies.h b/indra/llcommon/lldependencies.h
index e0294e271b..db2bbab8b0 100644
--- a/indra/llcommon/lldependencies.h
+++ b/indra/llcommon/lldependencies.h
@@ -34,13 +34,13 @@
 #include <vector>
 #include <set>
 #include <map>
-#include <stdexcept>
 #include <iosfwd>
 #include <boost/iterator/transform_iterator.hpp>
 #include <boost/iterator/indirect_iterator.hpp>
 #include <boost/range/iterator_range.hpp>
 #include <boost/function.hpp>
 #include <boost/bind.hpp>
+#include "llexception.h"
 
 /*****************************************************************************
 *   Utilities
@@ -106,9 +106,9 @@ public:
     /**
      * Exception thrown by sort() if there's a cycle
      */
-    struct Cycle: public std::runtime_error
+    struct Cycle: public LLException
     {
-        Cycle(const std::string& what): std::runtime_error(what) {}
+        Cycle(const std::string& what): LLException(what) {}
     };
 
     /**
@@ -124,8 +124,8 @@ public:
     virtual std::string describe(bool full=true) const;
 
 protected:
-    typedef std::vector< std::pair<int, int> > EdgeList;
-    typedef std::vector<int> VertexList;
+    typedef std::vector< std::pair<std::size_t, std::size_t> > EdgeList;
+    typedef std::vector<std::size_t> VertexList;
     VertexList topo_sort(int vertices, const EdgeList& edges) const;
 
     /**
@@ -508,7 +508,7 @@ public:
             // been explicitly added. Rely on std::map rejecting a second attempt
             // to insert the same key. Use the map's size() as the vertex number
             // to get a distinct value for each successful insertion.
-            typedef std::map<KEY, int> VertexMap;
+            typedef std::map<KEY, std::size_t> VertexMap;
             VertexMap vmap;
             // Nest each of these loops because !@#$%? MSVC warns us that its
             // former broken behavior has finally been fixed -- and our builds
diff --git a/indra/llcommon/llerror.cpp b/indra/llcommon/llerror.cpp
index 5ed348e13c..e6407ecf22 100644
--- a/indra/llcommon/llerror.cpp
+++ b/indra/llcommon/llerror.cpp
@@ -239,6 +239,14 @@ namespace
 {
 	std::string className(const std::type_info& type)
 	{
+		return LLError::Log::demangle(type.name());
+	}
+} // anonymous
+
+namespace LLError
+{
+	std::string Log::demangle(const char* mangled)
+	{
 #ifdef __GNUC__
 		// GCC: type_info::name() returns a mangled class name,st demangle
 
@@ -252,31 +260,34 @@ namespace
 			// but gcc 3.3 libstc++'s implementation of demangling is broken
 			// and fails without.
 			
-		char* name = abi::__cxa_demangle(type.name(),
+		char* name = abi::__cxa_demangle(mangled,
 										abi_name_buf, &abi_name_len, &status);
 			// this call can realloc the abi_name_buf pointer (!)
 
-		return name ? name : type.name();
+		return name ? name : mangled;
 
 #elif LL_WINDOWS
 		// DevStudio: type_info::name() includes the text "class " at the start
 
 		static const std::string class_prefix = "class ";
-
-		std::string name = type.name();
-		std::string::size_type p = name.find(class_prefix);
-		if (p == std::string::npos)
+		std::string name = mangled;
+		if (0 != name.compare(0, class_prefix.length(), class_prefix))
 		{
+			LL_DEBUGS() << "Did not see '" << class_prefix << "' prefix on '"
+					   << name << "'" << LL_ENDL;
 			return name;
 		}
 
-		return name.substr(p + class_prefix.size());
+		return name.substr(class_prefix.length());
 
-#else		
-		return type.name();
+#else
+		return mangled;
 #endif
 	}
+} // LLError
 
+namespace
+{
 	std::string functionName(const std::string& preprocessor_name)
 	{
 #if LL_WINDOWS
@@ -363,9 +374,8 @@ namespace
 
 	class Globals : public LLSingleton<Globals>
 	{
+		LLSINGLETON(Globals);
 	public:
-		Globals();
-
 		std::ostringstream messageStream;
 		bool messageStreamInUse;
 
@@ -438,11 +448,10 @@ namespace LLError
 
 	class Settings : public LLSingleton<Settings>
 	{
+		LLSINGLETON(Settings);
 	public:
-		Settings();
-
 		SettingsConfigPtr getSettingsConfig();
-	
+
 		void reset();
 		SettingsStoragePtr saveAndReset();
 		void restore(SettingsStoragePtr pSettingsStorage);
@@ -450,7 +459,7 @@ namespace LLError
 	private:
 		SettingsConfigPtr mSettingsConfig;
 	};
-	
+
 	SettingsConfig::SettingsConfig()
 		: LLRefCount(),
 		mPrintLocation(false),
@@ -475,8 +484,7 @@ namespace LLError
 		mRecorders.clear();
 	}
 
-	Settings::Settings()
-		: LLSingleton<Settings>(),
+	Settings::Settings():
 		mSettingsConfig(new SettingsConfig())
 	{
 	}
@@ -485,26 +493,31 @@ namespace LLError
 	{
 		return mSettingsConfig;
 	}
-	
+
 	void Settings::reset()
 	{
 		Globals::getInstance()->invalidateCallSites();
 		mSettingsConfig = new SettingsConfig();
 	}
-	
+
 	SettingsStoragePtr Settings::saveAndReset()
 	{
 		SettingsStoragePtr oldSettingsConfig(mSettingsConfig.get());
 		reset();
 		return oldSettingsConfig;
 	}
-	
+
 	void Settings::restore(SettingsStoragePtr pSettingsStorage)
 	{
 		Globals::getInstance()->invalidateCallSites();
 		SettingsConfigPtr newSettingsConfig(dynamic_cast<SettingsConfig *>(pSettingsStorage.get()));
 		mSettingsConfig = newSettingsConfig;
 	}
+
+	bool is_available()
+	{
+		return Settings::instanceExists() && Globals::instanceExists();
+	}
 }
 
 namespace LLError
@@ -921,11 +934,6 @@ namespace
 			
 			std::ostringstream message_stream;
 
-			if (show_location && (r->wantsLocation() || level == LLError::LEVEL_ERROR || s->mPrintLocation))
-			{
-				message_stream << site.mLocationString << " ";
-			}
-
 			if (show_time && r->wantsTime() && s->mTimeFunction != NULL)
 			{
 				message_stream << s->mTimeFunction() << " ";
@@ -933,17 +941,17 @@ namespace
 
 			if (show_level && r->wantsLevel())
             {
-				message_stream << site.mLevelString;
+				message_stream << site.mLevelString << " ";
             }
 				
 			if (show_tags && r->wantsTags())
 			{
 				message_stream << site.mTagString;
 			}
-			if ((show_level && r->wantsLevel())||
-                (show_tags && r->wantsTags()))
+
+            if (show_location && (r->wantsLocation() || level == LLError::LEVEL_ERROR || s->mPrintLocation))
             {
-                message_stream << " ";
+                message_stream << site.mLocationString << " ";
             }
 
 			if (show_function && r->wantsFunctionName())
@@ -1493,3 +1501,20 @@ namespace LLError
    }
 }
 
+bool debugLoggingEnabled(const std::string& tag)
+{
+    const char* tags[] = {tag.c_str()};
+    ::size_t tag_count = 1;
+    LLError::CallSite _site(LLError::LEVEL_DEBUG, __FILE__, __LINE__, 
+                            typeid(_LL_CLASS_TO_LOG), __FUNCTION__, false, tags, tag_count);
+    if (LL_UNLIKELY(_site.shouldLog()))
+    {
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+
diff --git a/indra/llcommon/llerror.h b/indra/llcommon/llerror.h
index 3beef65723..ceb1fd2c5f 100644
--- a/indra/llcommon/llerror.h
+++ b/indra/llcommon/llerror.h
@@ -174,7 +174,8 @@ namespace LLError
 			// not really a level
 			// used to indicate that no messages should be logged
 	};
-	
+	// If you change ELevel, please update llvlog() macro below.
+
 	/*	Macro support
 		The classes CallSite and Log are used by the logging macros below.
 		They are not intended for general use.
@@ -189,6 +190,7 @@ namespace LLError
 		static std::ostringstream* out();
 		static void flush(std::ostringstream* out, char* message);
 		static void flush(std::ostringstream*, const CallSite&);
+		static std::string demangle(const char* mangled);
 	};
 	
 	struct LL_COMMON_API CallSite
@@ -305,24 +307,38 @@ typedef LLError::NoClassInfo _LL_CLASS_TO_LOG;
 
 /////////////////////////////////
 // Error Logging Macros
-// See top of file for common usage.	
+// See top of file for common usage.
 /////////////////////////////////
 
-// this macro uses a one-shot do statement to avoid parsing errors when writing control flow statements
-// without braces:
-// if (condition) LL_INFOS() << "True" << LL_ENDL; else LL_INFOS()() << "False" << LL_ENDL
-
-#define lllog(level, once, ...)																	          \
-	do {                                                                                                  \
-		const char* tags[] = {"", ##__VA_ARGS__};													      \
-		::size_t tag_count = LL_ARRAY_SIZE(tags) - 1;													  \
-		static LLError::CallSite _site(                                                                   \
-		    level, __FILE__, __LINE__, typeid(_LL_CLASS_TO_LOG), __FUNCTION__, once, &tags[1], tag_count);\
-		if (LL_UNLIKELY(_site.shouldLog()))			                                                      \
-		{                                                                                                 \
-			std::ostringstream* _out = LLError::Log::out();                                               \
+// Instead of using LL_DEBUGS(), LL_INFOS() et al., it may be tempting to
+// directly code the lllog() macro so you can pass in the LLError::ELevel as a
+// variable. DON'T DO IT! The reason is that the first time control passes
+// through lllog(), it initializes a local static LLError::CallSite with that
+// *first* ELevel value. All subsequent visits will decide whether or not to
+// emit output based on the *first* ELevel value bound into that static
+// CallSite instance. Use LL_VLOGS() instead. lllog() assumes its ELevel
+// argument never varies.
+
+// this macro uses a one-shot do statement to avoid parsing errors when
+// writing control flow statements without braces:
+// if (condition) LL_INFOS() << "True" << LL_ENDL; else LL_INFOS()() << "False" << LL_ENDL;
+
+#define lllog(level, once, ...)                                         \
+	do {                                                                \
+		const char* tags[] = {"", ##__VA_ARGS__};                       \
+		static LLError::CallSite _site(lllog_site_args_(level, once, tags)); \
+		lllog_test_()
+
+#define lllog_test_()                                       \
+		if (LL_UNLIKELY(_site.shouldLog()))                 \
+		{                                                   \
+			std::ostringstream* _out = LLError::Log::out(); \
 			(*_out)
 
+#define lllog_site_args_(level, once, tags)                 \
+	level, __FILE__, __LINE__, typeid(_LL_CLASS_TO_LOG),    \
+	__FUNCTION__, once, &tags[1], LL_ARRAY_SIZE(tags)-1
+
 //Use this construct if you need to do computation in the middle of a
 //message:
 //	
@@ -363,4 +379,49 @@ typedef LLError::NoClassInfo _LL_CLASS_TO_LOG;
 #define LL_INFOS_ONCE(...)	lllog(LLError::LEVEL_INFO, true, ##__VA_ARGS__)
 #define LL_WARNS_ONCE(...)	lllog(LLError::LEVEL_WARN, true, ##__VA_ARGS__)
 
+// Use this if you need to pass LLError::ELevel as a variable.
+#define LL_VLOGS(level, ...)      llvlog(level, false, ##__VA_ARGS__)
+#define LL_VLOGS_ONCE(level, ...) llvlog(level, true,  ##__VA_ARGS__)
+
+// The problem with using lllog() with a variable level is that the first time
+// through, it initializes a static CallSite instance with whatever level you
+// pass. That first level is bound into the CallSite; the level parameter is
+// never again examined. One approach to variable level would be to
+// dynamically construct a CallSite instance every call -- which could get
+// expensive, depending on context. So instead, initialize a static CallSite
+// for each level value we support, then dynamically select the CallSite
+// instance for the passed level value.
+// Compare implementation to lllog() above.
+#define llvlog(level, once, ...)                                        \
+	do {                                                                \
+		const char* tags[] = {"", ##__VA_ARGS__};                       \
+		/* Need a static CallSite instance per expected ELevel value. */ \
+		/* Since we intend to index this array with the ELevel, */      \
+		/* _sites[0] should be ELevel(0), and so on -- avoid using */   \
+		/* ELevel symbolic names when initializing -- except for */     \
+		/* the last entry, which handles anything beyond the end. */    \
+		/* (Commented ELevel value names are from 2016-09-01.) */       \
+		/* Passing an ELevel past the end of this array is itself */    \
+		/* a fatal error, so ensure the last is LEVEL_ERROR. */         \
+		static LLError::CallSite _sites[] =                             \
+		{                                                               \
+			/* LEVEL_DEBUG */                                           \
+			LLError::CallSite(lllog_site_args_(LLError::ELevel(0), once, tags)), \
+			/* LEVEL_INFO */                                            \
+			LLError::CallSite(lllog_site_args_(LLError::ELevel(1), once, tags)), \
+			/* LEVEL_WARN */                                            \
+			LLError::CallSite(lllog_site_args_(LLError::ELevel(2), once, tags)), \
+			/* LEVEL_ERROR */                                           \
+			LLError::CallSite(lllog_site_args_(LLError::LEVEL_ERROR, once, tags)) \
+		};                                                              \
+		/* Clamp the passed 'level' to at most last entry */            \
+		std::size_t which((std::size_t(level) >= LL_ARRAY_SIZE(_sites)) ? \
+						  (LL_ARRAY_SIZE(_sites) - 1) : std::size_t(level)); \
+		/* selected CallSite *must* be named _site for LL_ENDL */       \
+		LLError::CallSite& _site(_sites[which]);                        \
+		lllog_test_()
+
+// Check at run-time whether logging is enabled, without generating output
+bool debugLoggingEnabled(const std::string& tag);
+
 #endif // LL_LLERROR_H
diff --git a/indra/llcommon/llerrorcontrol.h b/indra/llcommon/llerrorcontrol.h
index 56ac52e5de..56e84f7172 100644
--- a/indra/llcommon/llerrorcontrol.h
+++ b/indra/llcommon/llerrorcontrol.h
@@ -189,6 +189,11 @@ namespace LLError
 
 	LL_COMMON_API std::string abbreviateFile(const std::string& filePath);
 	LL_COMMON_API int shouldLogCallCount();
+
+	// Check whether Globals exists. This should only be used by LLSingleton
+	// infrastructure to avoid trying to log when our internal LLSingleton is
+	// unavailable -- circularity ensues.
+	LL_COMMON_API bool is_available();
 };
 
 #endif // LL_LLERRORCONTROL_H
diff --git a/indra/llcommon/lleventcoro.cpp b/indra/llcommon/lleventcoro.cpp
index 2d5f964deb..56367b8f54 100644
--- a/indra/llcommon/lleventcoro.cpp
+++ b/indra/llcommon/lleventcoro.cpp
@@ -39,6 +39,7 @@
 #include "llerror.h"
 #include "llcoros.h"
 #include "llmake.h"
+#include "llexception.h"
 
 #include "lleventfilter.h"
 
@@ -351,7 +352,7 @@ LLSD errorException(const LLEventWithID& result, const std::string& desc)
     // returning it, deliver it via exception.
     if (result.second)
     {
-        throw LLErrorEvent(desc, result.first);
+        LLTHROW(LLErrorEvent(desc, result.first));
     }
     // That way, our caller knows a simple return must be from the reply
     // pump (pump 0).
diff --git a/indra/llcommon/lleventcoro.h b/indra/llcommon/lleventcoro.h
index 87926c692d..84827aab4a 100644
--- a/indra/llcommon/lleventcoro.h
+++ b/indra/llcommon/lleventcoro.h
@@ -31,10 +31,10 @@
 
 #include <boost/optional.hpp>
 #include <string>
-#include <stdexcept>
 #include <utility>                  // std::pair
 #include "llevents.h"
 #include "llerror.h"
+#include "llexception.h"
 
 /**
  * Like LLListenerOrPumpName, this is a class intended for parameter lists:
@@ -234,11 +234,11 @@ LLSD errorException(const LLEventWithID& result, const std::string& desc);
  * because it's not an error in event processing: rather, this exception
  * announces an event that bears error information (for some other API).
  */
-class LL_COMMON_API LLErrorEvent: public std::runtime_error
+class LL_COMMON_API LLErrorEvent: public LLException
 {
 public:
     LLErrorEvent(const std::string& what, const LLSD& data):
-        std::runtime_error(what),
+        LLException(what),
         mData(data)
     {}
     virtual ~LLErrorEvent() throw() {}
diff --git a/indra/llcommon/llevents.cpp b/indra/llcommon/llevents.cpp
index 645c29d770..97270e4931 100644
--- a/indra/llcommon/llevents.cpp
+++ b/indra/llcommon/llevents.cpp
@@ -57,6 +57,7 @@
 #include "stringize.h"
 #include "llerror.h"
 #include "llsdutil.h"
+#include "llexception.h"
 #if LL_MSVC
 #pragma warning (disable : 4702)
 #endif
@@ -174,7 +175,7 @@ std::string LLEventPumps::registerNew(const LLEventPump& pump, const std::string
     // Unless we're permitted to tweak it, that's Bad.
     if (! tweak)
     {
-        throw LLEventPump::DupPumpName(std::string("Duplicate LLEventPump name '") + name + "'");
+        LLTHROW(LLEventPump::DupPumpName("Duplicate LLEventPump name '" + name + "'"));
     }
     // The passed name isn't unique, but we're permitted to tweak it. Find the
     // first decimal-integer suffix not already taken. The insert() attempt
@@ -275,6 +276,8 @@ LLEventPumps::~LLEventPumps()
 #pragma warning (push)
 #pragma warning (disable : 4355) // 'this' used in initializer list: yes, intentionally
 #endif
+const std::string LLEventPump::ANONYMOUS = std::string();
+
 
 LLEventPump::LLEventPump(const std::string& name, bool tweak):
     // Register every new instance with LLEventPumps
@@ -313,145 +316,162 @@ LLBoundListener LLEventPump::listen_impl(const std::string& name, const LLEventL
                                          const NameList& after,
                                          const NameList& before)
 {
-    // Check for duplicate name before connecting listener to mSignal
-    ConnectionMap::const_iterator found = mConnections.find(name);
-    // In some cases the user might disconnect a connection explicitly -- or
-    // might use LLEventTrackable to disconnect implicitly. Either way, we can
-    // end up retaining in mConnections a zombie connection object that's
-    // already been disconnected. Such a connection object can't be
-    // reconnected -- nor, in the case of LLEventTrackable, would we want to
-    // try, since disconnection happens with the destruction of the listener
-    // object. That means it's safe to overwrite a disconnected connection
-    // object with the new one we're attempting. The case we want to prevent
-    // is only when the existing connection object is still connected.
-    if (found != mConnections.end() && found->second.connected())
-    {
-        throw DupListenerName(std::string("Attempt to register duplicate listener name '") + name +
-                              "' on " + typeid(*this).name() + " '" + getName() + "'");
-    }
-    // Okay, name is unique, try to reconcile its dependencies. Specify a new
-    // "node" value that we never use for an mSignal placement; we'll fix it
-    // later.
-    DependencyMap::node_type& newNode = mDeps.add(name, -1.0, after, before);
-    // What if this listener has been added, removed and re-added? In that
-    // case newNode already has a non-negative value because we never remove a
-    // listener from mDeps. But keep processing uniformly anyway in case the
-    // listener was added back with different dependencies. Then mDeps.sort()
-    // would put it in a different position, and the old newNode placement
-    // value would be wrong, so we'd have to reassign it anyway. Trust that
-    // re-adding a listener with the same dependencies is the trivial case for
-    // mDeps.sort(): it can just replay its cache.
-    DependencyMap::sorted_range sorted_range;
-    try
-    {
-        // Can we pick an order that works including this new entry?
-        sorted_range = mDeps.sort();
-    }
-    catch (const DependencyMap::Cycle& e)
-    {
-        // No: the new node's after/before dependencies have made mDeps
-        // unsortable. If we leave the new node in mDeps, it will continue
-        // to screw up all future attempts to sort()! Pull it out.
-        mDeps.remove(name);
-        throw Cycle(std::string("New listener '") + name + "' on " + typeid(*this).name() +
-                    " '" + getName() + "' would cause cycle: " + e.what());
-    }
-    // Walk the list to verify that we haven't changed the order.
-    float previous = 0.0, myprev = 0.0;
-    DependencyMap::sorted_iterator mydmi = sorted_range.end(); // need this visible after loop
-    for (DependencyMap::sorted_iterator dmi = sorted_range.begin();
-         dmi != sorted_range.end(); ++dmi)
+    float nodePosition = 1.0;
+
+    // if the supplied name is empty we are not interested in the ordering mechanism 
+    // and can bypass attempting to find the optimal location to insert the new 
+    // listener.  We'll just tack it on to the end.
+    if (!name.empty()) // should be the same as testing against ANONYMOUS
     {
-        // Since we've added the new entry with an invalid placement,
-        // recognize it and skip it.
-        if (dmi->first == name)
+        // Check for duplicate name before connecting listener to mSignal
+        ConnectionMap::const_iterator found = mConnections.find(name);
+        // In some cases the user might disconnect a connection explicitly -- or
+        // might use LLEventTrackable to disconnect implicitly. Either way, we can
+        // end up retaining in mConnections a zombie connection object that's
+        // already been disconnected. Such a connection object can't be
+        // reconnected -- nor, in the case of LLEventTrackable, would we want to
+        // try, since disconnection happens with the destruction of the listener
+        // object. That means it's safe to overwrite a disconnected connection
+        // object with the new one we're attempting. The case we want to prevent
+        // is only when the existing connection object is still connected.
+        if (found != mConnections.end() && found->second.connected())
         {
-            // Remember the iterator belonging to our new node, and which
-            // placement value was 'previous' at that point.
-            mydmi = dmi;
-            myprev = previous;
-            continue;
+        LLTHROW(DupListenerName("Attempt to register duplicate listener name '" + name +
+                                "' on " + typeid(*this).name() + " '" + getName() + "'"));
         }
-        // If the new node has rearranged the existing nodes, we'll find
-        // that their placement values are no longer in increasing order.
-        if (dmi->second < previous)
+        // Okay, name is unique, try to reconcile its dependencies. Specify a new
+        // "node" value that we never use for an mSignal placement; we'll fix it
+        // later.
+        DependencyMap::node_type& newNode = mDeps.add(name, -1.0, after, before);
+        // What if this listener has been added, removed and re-added? In that
+        // case newNode already has a non-negative value because we never remove a
+        // listener from mDeps. But keep processing uniformly anyway in case the
+        // listener was added back with different dependencies. Then mDeps.sort()
+        // would put it in a different position, and the old newNode placement
+        // value would be wrong, so we'd have to reassign it anyway. Trust that
+        // re-adding a listener with the same dependencies is the trivial case for
+        // mDeps.sort(): it can just replay its cache.
+        DependencyMap::sorted_range sorted_range;
+        try
         {
-            // This is another scenario in which we'd better back out the
-            // newly-added node from mDeps -- but don't do it yet, we want to
-            // traverse the existing mDeps to report on it!
-            // Describe the change to the order of our listeners. Copy
-            // everything but the newest listener to a vector we can sort to
-            // obtain the old order.
-            typedef std::vector< std::pair<float, std::string> > SortNameList;
-            SortNameList sortnames;
-            for (DependencyMap::sorted_iterator cdmi(sorted_range.begin()), cdmend(sorted_range.end());
-                 cdmi != cdmend; ++cdmi)
+            // Can we pick an order that works including this new entry?
+            sorted_range = mDeps.sort();
+        }
+        catch (const DependencyMap::Cycle& e)
+        {
+            // No: the new node's after/before dependencies have made mDeps
+            // unsortable. If we leave the new node in mDeps, it will continue
+            // to screw up all future attempts to sort()! Pull it out.
+            mDeps.remove(name);
+        LLTHROW(Cycle("New listener '" + name + "' on " + typeid(*this).name() +
+                      " '" + getName() + "' would cause cycle: " + e.what()));
+        }
+        // Walk the list to verify that we haven't changed the order.
+        float previous = 0.0, myprev = 0.0;
+        DependencyMap::sorted_iterator mydmi = sorted_range.end(); // need this visible after loop
+        for (DependencyMap::sorted_iterator dmi = sorted_range.begin();
+            dmi != sorted_range.end(); ++dmi)
+        {
+            // Since we've added the new entry with an invalid placement,
+            // recognize it and skip it.
+            if (dmi->first == name)
             {
-                if (cdmi->first != name)
-                {
-                    sortnames.push_back(SortNameList::value_type(cdmi->second, cdmi->first));
-                }
+                // Remember the iterator belonging to our new node, and which
+                // placement value was 'previous' at that point.
+                mydmi = dmi;
+                myprev = previous;
+                continue;
             }
-            std::sort(sortnames.begin(), sortnames.end());
-            std::ostringstream out;
-            out << "New listener '" << name << "' on " << typeid(*this).name() << " '" << getName()
-                << "' would move previous listener '" << dmi->first << "'\nwas: ";
-            SortNameList::const_iterator sni(sortnames.begin()), snend(sortnames.end());
-            if (sni != snend)
+            // If the new node has rearranged the existing nodes, we'll find
+            // that their placement values are no longer in increasing order.
+            if (dmi->second < previous)
             {
-                out << sni->second;
-                while (++sni != snend)
+                // This is another scenario in which we'd better back out the
+                // newly-added node from mDeps -- but don't do it yet, we want to
+                // traverse the existing mDeps to report on it!
+                // Describe the change to the order of our listeners. Copy
+                // everything but the newest listener to a vector we can sort to
+                // obtain the old order.
+                typedef std::vector< std::pair<float, std::string> > SortNameList;
+                SortNameList sortnames;
+                for (DependencyMap::sorted_iterator cdmi(sorted_range.begin()), cdmend(sorted_range.end());
+                    cdmi != cdmend; ++cdmi)
                 {
-                    out << ", " << sni->second;
+                    if (cdmi->first != name)
+                    {
+                        sortnames.push_back(SortNameList::value_type(cdmi->second, cdmi->first));
+                    }
                 }
-            }
-            out << "\nnow: ";
-            DependencyMap::sorted_iterator ddmi(sorted_range.begin()), ddmend(sorted_range.end());
-            if (ddmi != ddmend)
-            {
-                out << ddmi->first;
-                while (++ddmi != ddmend)
+                std::sort(sortnames.begin(), sortnames.end());
+                std::ostringstream out;
+                out << "New listener '" << name << "' on " << typeid(*this).name() << " '" << getName()
+                    << "' would move previous listener '" << dmi->first << "'\nwas: ";
+                SortNameList::const_iterator sni(sortnames.begin()), snend(sortnames.end());
+                if (sni != snend)
                 {
-                    out << ", " << ddmi->first;
+                    out << sni->second;
+                    while (++sni != snend)
+                    {
+                        out << ", " << sni->second;
+                    }
                 }
+                out << "\nnow: ";
+                DependencyMap::sorted_iterator ddmi(sorted_range.begin()), ddmend(sorted_range.end());
+                if (ddmi != ddmend)
+                {
+                    out << ddmi->first;
+                    while (++ddmi != ddmend)
+                    {
+                        out << ", " << ddmi->first;
+                    }
+                }
+                // NOW remove the offending listener node.
+                mDeps.remove(name);
+                // Having constructed a description of the order change, inform caller.
+            LLTHROW(OrderChange(out.str()));
             }
-            // NOW remove the offending listener node.
-            mDeps.remove(name);
-            // Having constructed a description of the order change, inform caller.
-            throw OrderChange(out.str());
+            // This node becomes the previous one.
+            previous = dmi->second;
         }
-        // This node becomes the previous one.
-        previous = dmi->second;
-    }
-    // We just got done with a successful mDeps.add(name, ...) call. We'd
-    // better have found 'name' somewhere in that sorted list!
-    assert(mydmi != sorted_range.end());
-    // Four cases:
-    // 0. name is the only entry: placement 1.0
-    // 1. name is the first of several entries: placement (next placement)/2
-    // 2. name is between two other entries: placement (myprev + (next placement))/2
-    // 3. name is the last entry: placement ceil(myprev) + 1.0
-    // Since we've cleverly arranged for myprev to be 0.0 if name is the
-    // first entry, this folds down to two cases. Case 1 is subsumed by
-    // case 2, and case 0 is subsumed by case 3. So we need only handle
-    // cases 2 and 3, which means we need only detect whether name is the
-    // last entry. Increment mydmi to see if there's anything beyond.
-    if (++mydmi != sorted_range.end())
-    {
-        // The new node isn't last. Place it between the previous node and
-        // the successor.
-        newNode = (myprev + mydmi->second)/2.f;
-    }
-    else
-    {
-        // The new node is last. Bump myprev up to the next integer, add
-        // 1.0 and use that.
-        newNode = std::ceil(myprev) + 1.f;
+        // We just got done with a successful mDeps.add(name, ...) call. We'd
+        // better have found 'name' somewhere in that sorted list!
+        assert(mydmi != sorted_range.end());
+        // Four cases:
+        // 0. name is the only entry: placement 1.0
+        // 1. name is the first of several entries: placement (next placement)/2
+        // 2. name is between two other entries: placement (myprev + (next placement))/2
+        // 3. name is the last entry: placement ceil(myprev) + 1.0
+        // Since we've cleverly arranged for myprev to be 0.0 if name is the
+        // first entry, this folds down to two cases. Case 1 is subsumed by
+        // case 2, and case 0 is subsumed by case 3. So we need only handle
+        // cases 2 and 3, which means we need only detect whether name is the
+        // last entry. Increment mydmi to see if there's anything beyond.
+        if (++mydmi != sorted_range.end())
+        {
+            // The new node isn't last. Place it between the previous node and
+            // the successor.
+            newNode = (myprev + mydmi->second) / 2.f;
+        }
+        else
+        {
+            // The new node is last. Bump myprev up to the next integer, add
+            // 1.0 and use that.
+            newNode = std::ceil(myprev) + 1.f;
+        }
+
+        nodePosition = newNode;
     }
     // Now that newNode has a value that places it appropriately in mSignal,
     // connect it.
-    LLBoundListener bound = mSignal->connect(newNode, listener);
-    mConnections[name] = bound;
+    LLBoundListener bound = mSignal->connect(nodePosition, listener);
+    
+    if (!name.empty())
+    {   // note that we are not tracking anonymous listeners here either.
+        // This means that it is the caller's responsibility to either assign 
+        // to a TempBoundListerer (scoped_connection) or manually disconnect 
+        // when done. 
+        mConnections[name] = bound;
+    }
     return bound;
 }
 
@@ -608,7 +628,7 @@ bool LLListenerOrPumpName::operator()(const LLSD& event) const
 {
     if (! mListener)
     {
-        throw Empty("attempting to call uninitialized");
+        LLTHROW(Empty("attempting to call uninitialized"));
     }
     return (*mListener)(event);
 }
diff --git a/indra/llcommon/llevents.h b/indra/llcommon/llevents.h
index ba4fcd766e..7cff7dfd45 100644
--- a/indra/llcommon/llevents.h
+++ b/indra/llcommon/llevents.h
@@ -37,7 +37,6 @@
 #include <set>
 #include <vector>
 #include <deque>
-#include <stdexcept>
 #if LL_WINDOWS
 	#pragma warning (push)
 	#pragma warning (disable : 4263) // boost::signals2::expired_slot::what() has const mismatch
@@ -62,6 +61,7 @@
 #include "llsingleton.h"
 #include "lldependencies.h"
 #include "llstl.h"
+#include "llexception.h"
 
 /*==========================================================================*|
 // override this to allow binding free functions with more parameters
@@ -95,12 +95,32 @@ struct LLStopWhenHandled
     result_type operator()(InputIterator first, InputIterator last) const
     {
         for (InputIterator si = first; si != last; ++si)
-		{
-            if (*si)
-			{
-                return true;
-			}
-		}
+        {
+            try
+            {
+                if (*si)
+                {
+                    return true;
+                }
+            }
+            catch (const LLContinueError&)
+            {
+                // We catch LLContinueError here because an LLContinueError-
+                // based exception means the viewer as a whole should carry on
+                // to the best of our ability. Therefore subsequent listeners
+                // on the same LLEventPump should still receive this event.
+
+                // The iterator passed to a boost::signals2 Combiner is very
+                // clever, but provides no contextual information. We would
+                // very much like to be able to log the name of the LLEventPump
+                // plus the name of this particular listener, but alas.
+                LOG_UNHANDLED_EXCEPTION("LLEventPump");
+            }
+            // We do NOT catch (...) here because we might as well let it
+            // propagate out to the generic handler. If we were able to log
+            // context information here, that would be great, but we can't, so
+            // there's no point.
+        }
         return false;
     }
 };
@@ -188,10 +208,10 @@ public:
     bool operator()(const LLSD& event) const;
 
     /// exception if you try to call when empty
-    struct Empty: public std::runtime_error
+    struct Empty: public LLException
     {
         Empty(const std::string& what):
-            std::runtime_error(std::string("LLListenerOrPumpName::Empty: ") + what) {}
+            LLException(std::string("LLListenerOrPumpName::Empty: ") + what) {}
     };
 
 private:
@@ -209,7 +229,7 @@ class LLEventPump;
  */
 class LL_COMMON_API LLEventPumps: public LLSingleton<LLEventPumps>
 {
-    friend class LLSingleton<LLEventPumps>;
+    LLSINGLETON(LLEventPumps);
 public:
     /**
      * Find or create an LLEventPump instance with a specific name. We return
@@ -252,7 +272,6 @@ private:
     void unregister(const LLEventPump&);
 
 private:
-    LLEventPumps();
     ~LLEventPumps();
 
 testable:
@@ -365,16 +384,18 @@ typedef boost::signals2::trackable LLEventTrackable;
 class LL_COMMON_API LLEventPump: public LLEventTrackable
 {
 public:
+    static const std::string ANONYMOUS; // constant for anonymous listeners.
+
     /**
      * Exception thrown by LLEventPump(). You are trying to instantiate an
      * LLEventPump (subclass) using the same name as some other instance, and
      * you didn't pass <tt>tweak=true</tt> to permit it to generate a unique
      * variant.
      */
-    struct DupPumpName: public std::runtime_error
+    struct DupPumpName: public LLException
     {
         DupPumpName(const std::string& what):
-            std::runtime_error(std::string("DupPumpName: ") + what) {}
+            LLException(std::string("DupPumpName: ") + what) {}
     };
 
     /**
@@ -399,9 +420,9 @@ public:
     /// group exceptions thrown by listen(). We use exceptions because these
     /// particular errors are likely to be coding errors, found and fixed by
     /// the developer even before preliminary checkin.
-    struct ListenError: public std::runtime_error
+    struct ListenError: public LLException
     {
-        ListenError(const std::string& what): std::runtime_error(what) {}
+        ListenError(const std::string& what): LLException(what) {}
     };
     /**
      * exception thrown by listen(). You are attempting to register a
@@ -476,6 +497,12 @@ public:
      * instantiate your listener, then passing the same name on each listen()
      * call, allows us to optimize away the second and subsequent dependency
      * sorts.
+     * 
+     * If name is set to LLEventPump::ANONYMOUS listen will bypass the entire 
+     * dependency and ordering calculation. In this case, it is critical that 
+     * the result be assigned to a LLTempBoundListener or the listener is 
+     * manually disconnected when no longer needed since there will be no
+     * way to later find and disconnect this listener manually.
      *
      * If (as is typical) you pass a <tt>boost::bind()</tt> expression as @a
      * listener, listen() will inspect the components of that expression. If a
diff --git a/indra/llcommon/llexception.cpp b/indra/llcommon/llexception.cpp
new file mode 100644
index 0000000000..b32ec2c9c9
--- /dev/null
+++ b/indra/llcommon/llexception.cpp
@@ -0,0 +1,55 @@
+/**
+ * @file   llexception.cpp
+ * @author Nat Goodspeed
+ * @date   2016-08-12
+ * @brief  Implementation for llexception.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llexception.h"
+// STL headers
+// std headers
+#include <typeinfo>
+// external library headers
+#include <boost/exception/diagnostic_information.hpp>
+// other Linden headers
+#include "llerror.h"
+#include "llerrorcontrol.h"
+
+namespace {
+// used by crash_on_unhandled_exception_() and log_unhandled_exception_()
+void log_unhandled_exception_(LLError::ELevel level,
+                              const char* file, int line, const char* pretty_function,
+                              const std::string& context)
+{
+    // log same message but allow caller-specified severity level
+    LL_VLOGS(level, "LLException") << LLError::abbreviateFile(file)
+        << "(" << line << "): Unhandled exception caught in " << pretty_function;
+    if (! context.empty())
+    {
+        LL_CONT << ": " << context;
+    }
+    LL_CONT << ":\n" << boost::current_exception_diagnostic_information() << LL_ENDL;
+}
+}
+
+void crash_on_unhandled_exception_(const char* file, int line, const char* pretty_function,
+                                   const std::string& context)
+{
+    // LL_ERRS() terminates and propagates message into crash dump.
+    log_unhandled_exception_(LLError::LEVEL_ERROR, file, line, pretty_function, context);
+}
+
+void log_unhandled_exception_(const char* file, int line, const char* pretty_function,
+                              const std::string& context)
+{
+    // Use LL_WARNS() because we seriously do not expect this to happen
+    // routinely, but we DO expect to return from this function.
+    log_unhandled_exception_(LLError::LEVEL_WARN, file, line, pretty_function, context);
+}
diff --git a/indra/llcommon/llexception.h b/indra/llcommon/llexception.h
new file mode 100644
index 0000000000..dfcb7c192f
--- /dev/null
+++ b/indra/llcommon/llexception.h
@@ -0,0 +1,85 @@
+/**
+ * @file   llexception.h
+ * @author Nat Goodspeed
+ * @date   2016-06-29
+ * @brief  Types needed for generic exception handling
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLEXCEPTION_H)
+#define LL_LLEXCEPTION_H
+
+#include <stdexcept>
+#include <boost/exception/exception.hpp>
+#include <boost/throw_exception.hpp>
+#include <boost/current_function.hpp>
+
+// "Found someone who can comfort me
+//  But there are always exceptions..."
+//  - Empty Pages, Traffic, from John Barleycorn (1970)
+//    https://www.youtube.com/watch?v=dRH0CGVK7ic
+
+/**
+ * LLException is intended as the common base class from which all
+ * viewer-specific exceptions are derived. Rationale for why it's derived from
+ * both std::exception and boost::exception is explained in
+ * tests/llexception_test.cpp.
+ *
+ * boost::current_exception_diagnostic_information() is quite wonderful: if
+ * all we need to do with an exception is log it, in most places we should
+ * catch (...) and log boost::current_exception_diagnostic_information().
+ * See CRASH_ON_UNHANDLED_EXCEPTION() and LOG_UNHANDLED_EXCEPTION() below.
+ *
+ * There may be circumstances in which it would be valuable to distinguish an
+ * exception explicitly thrown by viewer code from an exception thrown by
+ * (say) a third-party library. Catching (const LLException&) supports such
+ * usage. However, most of the value of this base class is in the
+ * diagnostic_information() available via Boost.Exception.
+ */
+struct LLException:
+    public std::runtime_error,
+    public boost::exception
+{
+    LLException(const std::string& what):
+        std::runtime_error(what)
+    {}
+};
+
+/**
+ * The point of LLContinueError is to distinguish exceptions that need not
+ * terminate the whole viewer session. In general, an uncaught exception will
+ * be logged and will crash the viewer. However, though an uncaught exception
+ * derived from LLContinueError will still be logged, the viewer will attempt
+ * to continue processing.
+ */
+struct LLContinueError: public LLException
+{
+    LLContinueError(const std::string& what):
+        LLException(what)
+    {}
+};
+
+/**
+ * Please use LLTHROW() to throw viewer exceptions whenever possible. This
+ * enriches the exception's diagnostic_information() with the source file,
+ * line and containing function of the LLTHROW() macro.
+ */
+// Currently we implement that using BOOST_THROW_EXCEPTION(). Wrap it in
+// LLTHROW() in case we ever want to revisit that implementation decision.
+#define LLTHROW(x) BOOST_THROW_EXCEPTION(x)
+
+/// Call this macro from a catch (...) clause
+#define CRASH_ON_UNHANDLED_EXCEPTION(CONTEXT) \
+     crash_on_unhandled_exception_(__FILE__, __LINE__, BOOST_CURRENT_FUNCTION, CONTEXT)
+void crash_on_unhandled_exception_(const char*, int, const char*, const std::string&);
+
+/// Call this from a catch (const LLContinueError&) clause, or from a catch
+/// (...) clause in which you do NOT want the viewer to crash.
+#define LOG_UNHANDLED_EXCEPTION(CONTEXT) \
+     log_unhandled_exception_(__FILE__, __LINE__, BOOST_CURRENT_FUNCTION, CONTEXT)
+void log_unhandled_exception_(const char*, int, const char*, const std::string&);
+
+#endif /* ! defined(LL_LLEXCEPTION_H) */
diff --git a/indra/llcommon/llfasttimer.h b/indra/llcommon/llfasttimer.h
index 2370253078..2024d707da 100644
--- a/indra/llcommon/llfasttimer.h
+++ b/indra/llcommon/llfasttimer.h
@@ -90,33 +90,15 @@ public:
 #if LL_FASTTIMER_USE_RDTSC
 	static U32 getCPUClockCount32()
 	{
-		U32 ret_val;
-		__asm
-		{
-			_emit   0x0f
-				_emit   0x31
-				shr eax,8
-				shl edx,24
-				or eax, edx
-				mov dword ptr [ret_val], eax
-		}
-		return ret_val;
+		unsigned __int64 val = __rdtsc();
+		val = val >> 8;
+		return static_cast<U32>(val);
 	}
 
 	// return full timer value, *not* shifted by 8 bits
 	static U64 getCPUClockCount64()
 	{
-		U64 ret_val;
-		__asm
-		{
-			_emit   0x0f
-				_emit   0x31
-				mov eax,eax
-				mov edx,edx
-				mov dword ptr [ret_val+4], edx
-				mov dword ptr [ret_val], eax
-		}
-		return ret_val;
+		return static_cast<U64>( __rdtsc() );
 	}
 
 #else
@@ -173,16 +155,16 @@ public:
 	// Mac+Linux+Solaris FAST x86 implementation of CPU clock
 	static U32 getCPUClockCount32()
 	{
-		U64 x;
-		__asm__ volatile (".byte 0x0f, 0x31": "=A"(x));
-		return (U32)(x >> 8);
+		U32 low(0),high(0);
+		__asm__ volatile (".byte 0x0f, 0x31": "=a"(low), "=d"(high) );
+		return (low>>8) | (high<<24);
 	}
 
 	static U64 getCPUClockCount64()
 	{
-		U64 x;
-		__asm__ volatile (".byte 0x0f, 0x31": "=A"(x));
-		return x;
+		U32 low(0),high(0);
+		__asm__ volatile (".byte 0x0f, 0x31": "=a"(low), "=d"(high) );
+		return (U64)low | ( ((U64)high) << 32);
 	}
 
 #endif
@@ -296,7 +278,16 @@ LL_FORCE_INLINE BlockTimer::BlockTimer(BlockTimerStatHandle& timer)
 {
 #if LL_FAST_TIMER_ON
 	BlockTimerStackRecord* cur_timer_data = LLThreadLocalSingletonPointer<BlockTimerStackRecord>::getInstance();
-	if (!cur_timer_data) return;
+	if (!cur_timer_data)
+	{
+		// How likely is it that
+		// LLThreadLocalSingletonPointer<T>::getInstance() will return NULL?
+		// Even without researching, what we can say is that if we exit
+		// without setting mStartTime at all, gcc 4.7 produces (fatal)
+		// warnings about a possibly-uninitialized data member.
+		mStartTime = 0;
+		return;
+	}
 	TimeBlockAccumulator& accumulator = timer.getCurrentAccumulator();
 	accumulator.mActiveCount++;
 	// keep current parent as long as it is active when we are
diff --git a/indra/llcommon/llfile.cpp b/indra/llcommon/llfile.cpp
index 873a7bce25..7b559861bb 100644
--- a/indra/llcommon/llfile.cpp
+++ b/indra/llcommon/llfile.cpp
@@ -239,7 +239,7 @@ int	LLFile::close(LLFILE * file)
 }
 
 
-int	LLFile::remove(const std::string& filename)
+int	LLFile::remove(const std::string& filename, int supress_error)
 {
 #if	LL_WINDOWS
 	std::string utf8filename = filename;
@@ -248,7 +248,7 @@ int	LLFile::remove(const std::string& filename)
 #else
 	int rc = ::remove(filename.c_str());
 #endif
-	return warnif("remove", filename, rc);
+	return warnif("remove", filename, rc, supress_error);
 }
 
 int	LLFile::rename(const std::string& filename, const std::string& newname)
diff --git a/indra/llcommon/llfile.h b/indra/llcommon/llfile.h
index 3e25228aeb..37eb75881c 100644
--- a/indra/llcommon/llfile.h
+++ b/indra/llcommon/llfile.h
@@ -45,7 +45,7 @@ typedef FILE	LLFILE;
 typedef struct _stat	llstat;
 #else
 typedef struct stat		llstat;
-#include <bits/postypes.h>
+#include <sys/types.h>
 #endif
 
 #ifndef S_ISREG
@@ -72,7 +72,7 @@ public:
 	static	int		mkdir(const std::string& filename, int perms = 0700);
 
 	static	int		rmdir(const std::string& filename);
-	static	int		remove(const std::string& filename);
+	static	int		remove(const std::string& filename, int supress_error = 0);
 	static	int		rename(const std::string& filename,const std::string&	newname);
 	static  bool	copy(const std::string from, const std::string to);
 
diff --git a/indra/llcommon/llhandle.h b/indra/llcommon/llhandle.h
index 401e4d759a..feb5f41848 100644
--- a/indra/llcommon/llhandle.h
+++ b/indra/llcommon/llhandle.h
@@ -28,8 +28,11 @@
 #define LLHANDLE_H
 
 #include "llpointer.h"
+#include "llexception.h"
+#include <stdexcept>
 #include <boost/type_traits/is_convertible.hpp>
 #include <boost/utility/enable_if.hpp>
+#include <boost/throw_exception.hpp>
 
 /**
  * Helper object for LLHandle. Don't instantiate these directly, used
@@ -213,4 +216,82 @@ private:
 	mutable LLRootHandle<T> mHandle;
 };
 
+
+
+class LLCheckedHandleBase
+{
+public:
+    class Stale : public LLException
+    {
+    public:
+        Stale() :
+            LLException("Attempt to access stale handle.")
+        {}
+    };
+
+protected:
+    LLCheckedHandleBase() { }
+
+};
+
+/**
+ * This is a simple wrapper for Handles, allowing direct calls to the underlying 
+ * pointer. The checked handle will throw a Stale if an attempt 
+ * is made to access the object referenced by the handle and that object has 
+ * been destroyed.
+ **/
+template <typename T> 
+class LLCheckedHandle: public LLCheckedHandleBase
+{
+public:
+
+    LLCheckedHandle(LLHandle<T> handle):
+        mHandle(handle)
+    { }
+
+    /**
+     * Test the underlying handle.  If it is no longer valid, throw a Stale exception.
+     */
+    void check() const
+    {
+        T* ptr = mHandle.get();
+        if (!ptr)
+            BOOST_THROW_EXCEPTION(Stale());
+    }
+
+    /**
+     * Cast back to an appropriate handle
+     */
+    operator LLHandle<T>() const
+    {
+        return mHandle;
+    }
+
+    /**
+     * Converts the LLCheckedHandle to a bool. Allows for if (chkdHandle) {} 
+     * Does not throw.
+     */
+    /*explicit*/ operator bool() const // explicit conversion operator not available with Linux compiler
+    {
+        return (mHandle.get() != NULL);
+    }
+
+    /**
+     * Attempt to call a method or access a member in the structure referenced 
+     * by the handle.  If the handle no longer points to a valid structure 
+     * throw a Stale.
+     */
+    T* operator ->() const
+    {
+        T* ptr = mHandle.get();
+        if (!ptr)
+            BOOST_THROW_EXCEPTION(Stale());
+        return ptr;
+    }
+
+private:
+
+    LLHandle<T> mHandle;
+};
+
 #endif
diff --git a/indra/llcommon/llheteromap.cpp b/indra/llcommon/llheteromap.cpp
new file mode 100644
index 0000000000..7c19196e0c
--- /dev/null
+++ b/indra/llcommon/llheteromap.cpp
@@ -0,0 +1,32 @@
+/**
+ * @file   llheteromap.cpp
+ * @author Nat Goodspeed
+ * @date   2016-10-12
+ * @brief  Implementation for llheteromap.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llheteromap.h"
+// STL headers
+// std headers
+// external library headers
+// other Linden headers
+
+LLHeteroMap::~LLHeteroMap()
+{
+    // For each entry in our map, we must call its deleter, which is the only
+    // record we have of its original type.
+    for (TypeMap::iterator mi(mMap.begin()), me(mMap.end()); mi != me; ++mi)
+    {
+        // mi->second is the std::pair; mi->second.first is the void*;
+        // mi->second.second points to the deleter function
+        (mi->second.second)(mi->second.first);
+        mi->second.first = NULL;
+    }
+}
diff --git a/indra/llcommon/llheteromap.h b/indra/llcommon/llheteromap.h
new file mode 100644
index 0000000000..7e96172333
--- /dev/null
+++ b/indra/llcommon/llheteromap.h
@@ -0,0 +1,95 @@
+/**
+ * @file   llheteromap.h
+ * @author Nat Goodspeed
+ * @date   2016-10-12
+ * @brief  Map capable of storing objects of diverse types, looked up by type.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLHETEROMAP_H)
+#define LL_LLHETEROMAP_H
+
+#include <typeinfo>
+#include <utility>                  // std::pair
+#include <map>
+
+/**
+ * LLHeteroMap addresses an odd requirement. Usually when you want to put
+ * objects of different classes into a runtime collection of any kind, you
+ * derive them all from a common base class and store pointers to that common
+ * base class.
+ *
+ * LLInitParam::BaseBlock uses disturbing raw-pointer arithmetic to find data
+ * members in its subclasses. It seems that no BaseBlock subclass can be
+ * stored in a polymorphic class of any kind: the presence of a vtbl pointer
+ * in the layout silently throws off the reinterpret_cast arithmetic. Bad
+ * Things result. (Many thanks to Nicky D for this analysis!)
+ *
+ * LLHeteroMap collects objects WITHOUT a common base class, retrieves them by
+ * object type and destroys them when the LLHeteroMap is destroyed.
+ */
+class LLHeteroMap
+{
+public:
+    ~LLHeteroMap();
+
+    /// find or create
+    template <class T>
+    T& obtain()
+    {
+        // Look up map entry by typeid(T). We don't simply use mMap[typeid(T)]
+        // because that requires default-constructing T on every lookup. For
+        // some kinds of T, that could be expensive.
+        TypeMap::iterator found = mMap.find(&typeid(T));
+        if (found == mMap.end())
+        {
+            // Didn't find typeid(T). Create an entry. Because we're storing
+            // only a void* in the map, discarding type information, make sure
+            // we capture that type information in our deleter.
+            void* ptr = new T();
+            void (*dlfn)(void*) = &deleter<T>;
+            std::pair<TypeMap::iterator, bool> inserted =
+                mMap.insert(TypeMap::value_type(&typeid(T),
+                    TypeMap::mapped_type(ptr, dlfn)));
+            // Okay, now that we have an entry, claim we found it.
+            found = inserted.first;
+        }
+        // found->second is the std::pair; second.first is the void*
+        // pointer to the object in question. Cast it to correct type and
+        // dereference it.
+        return *(static_cast<T*>(found->second.first));
+    }
+
+private:
+    template <class T>
+    static
+    void deleter(void* p)
+    {
+        delete static_cast<T*>(p);
+    }
+
+    // Comparing two std::type_info* values is tricky, because the standard
+    // does not guarantee that there will be only one type_info instance for a
+    // given type. In other words, &typeid(A) in one part of the program may
+    // not always equal &typeid(A) in some other part. Use special comparator.
+    struct type_info_ptr_comp
+    {
+        bool operator()(const std::type_info* lhs, const std::type_info* rhs) const
+        {
+            return lhs->before(*rhs);
+        }
+    };
+
+    // What we actually store is a map from std::type_info (permitting lookup
+    // by object type) to a void* pointer to the object PLUS its deleter.
+    typedef std::map<
+        const std::type_info*, std::pair<void*, void (*)(void*)>,
+        type_info_ptr_comp>
+    TypeMap;
+    TypeMap mMap;
+};
+
+#endif /* ! defined(LL_LLHETEROMAP_H) */
diff --git a/indra/llcommon/llinitdestroyclass.cpp b/indra/llcommon/llinitdestroyclass.cpp
new file mode 100644
index 0000000000..e6382a7924
--- /dev/null
+++ b/indra/llcommon/llinitdestroyclass.cpp
@@ -0,0 +1,30 @@
+/**
+ * @file   llinitdestroyclass.cpp
+ * @author Nat Goodspeed
+ * @date   2016-08-30
+ * @brief  Implementation for llinitdestroyclass.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llinitdestroyclass.h"
+// STL headers
+// std headers
+// external library headers
+// other Linden headers
+#include "llerror.h"
+
+void LLCallbackRegistry::fireCallbacks() const
+{
+	for (FuncList::const_iterator fi = mCallbacks.begin(), fe = mCallbacks.end();
+		 fi != fe; ++fi)
+	{
+		LL_INFOS("LLInitDestroyClass") << "calling " << fi->first << "()" << LL_ENDL;
+		fi->second();
+	}
+}
diff --git a/indra/llcommon/llinitdestroyclass.h b/indra/llcommon/llinitdestroyclass.h
new file mode 100644
index 0000000000..5f979614fe
--- /dev/null
+++ b/indra/llcommon/llinitdestroyclass.h
@@ -0,0 +1,175 @@
+/**
+ * @file   llinitdestroyclass.h
+ * @author Nat Goodspeed
+ * @date   2015-05-27
+ * @brief  LLInitClass / LLDestroyClass mechanism
+ *
+ * The LLInitClass template, extracted from llui.h, ensures that control will
+ * reach a static initClass() method. LLDestroyClass does the same for a
+ * static destroyClass() method.
+ *
+ * The distinguishing characteristics of these templates are:
+ *
+ * - All LLInitClass<T>::initClass() methods are triggered by an explicit call
+ *   to LLInitClassList::instance().fireCallbacks(). Presumably this call
+ *   happens sometime after all static objects in the program have been
+ *   initialized. In other words, each LLInitClass<T>::initClass() method
+ *   should be able to make some assumptions about global program state.
+ *
+ * - Similarly, LLDestroyClass<T>::destroyClass() methods are triggered by
+ *   LLDestroyClassList::instance().fireCallbacks(). Again, presumably this
+ *   happens at a well-defined moment in the program's shutdown sequence.
+ *
+ * - The initClass() calls happen in an unspecified sequence. You may not rely
+ *   on the relative ordering of LLInitClass<T>::initClass() versus another
+ *   LLInitClass<U>::initClass() method. If you need such a guarantee, use
+ *   LLSingleton instead and make the dependency explicit.
+ *
+ * - Similarly, LLDestroyClass<T>::destroyClass() may happen either before or
+ *   after LLDestroyClass<U>::destroyClass(). You cannot rely on that order.
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLINITDESTROYCLASS_H)
+#define LL_LLINITDESTROYCLASS_H
+
+#include "llsingleton.h"
+#include <boost/function.hpp>
+#include <typeinfo>
+#include <vector>
+#include <utility>                  // std::pair
+
+/**
+ * LLCallbackRegistry is an implementation detail base class for
+ * LLInitClassList and LLDestroyClassList. It accumulates the initClass() or
+ * destroyClass() callbacks for registered classes.
+ */
+class LLCallbackRegistry
+{
+public:
+	typedef boost::function<void()> func_t;
+
+	void registerCallback(const std::string& name, const func_t& func)
+	{
+		mCallbacks.push_back(FuncList::value_type(name, func));
+	}
+
+	void fireCallbacks() const;
+
+private:
+	// Arguably this should be a boost::signals2::signal, which is, after all,
+	// a sequence of callables. We manage it by hand so we can log a name for
+	// each registered function we call.
+	typedef std::vector< std::pair<std::string, func_t> > FuncList;
+	FuncList mCallbacks;
+};
+
+/**
+ * LLInitClassList is the LLCallbackRegistry for LLInitClass. It stores the
+ * registered initClass() methods. It must be an LLSingleton because
+ * LLInitClass registers its initClass() method at static construction time
+ * (before main()), requiring LLInitClassList to be fully constructed on
+ * demand regardless of module initialization order.
+ */
+class LLInitClassList : 
+	public LLCallbackRegistry, 
+	public LLSingleton<LLInitClassList>
+{
+	LLSINGLETON_EMPTY_CTOR(LLInitClassList);
+};
+
+/**
+ * LLDestroyClassList is the LLCallbackRegistry for LLDestroyClass. It stores
+ * the registered destroyClass() methods. It must be an LLSingleton because
+ * LLDestroyClass registers its destroyClass() method at static construction
+ * time (before main()), requiring LLDestroyClassList to be fully constructed
+ * on demand regardless of module initialization order.
+ */
+class LLDestroyClassList : 
+	public LLCallbackRegistry, 
+	public LLSingleton<LLDestroyClassList>
+{
+	LLSINGLETON_EMPTY_CTOR(LLDestroyClassList);
+};
+
+/**
+ * LLRegisterWith is an implementation detail for LLInitClass and
+ * LLDestroyClass. It is intended to be used as a static class member whose
+ * constructor registers the specified callback with the LLMumbleClassList
+ * singleton registry specified as the template argument.
+ */
+template<typename T>
+class LLRegisterWith
+{
+public:
+	LLRegisterWith(const std::string& name, const LLCallbackRegistry::func_t& func)
+	{
+		T::instance().registerCallback(name, func);
+	}
+
+	// this avoids a MSVC bug where non-referenced static members are "optimized" away
+	// even if their constructors have side effects
+	S32 reference()
+	{
+		S32 dummy;
+		dummy = 0;
+		return dummy;
+	}
+};
+
+/**
+ * Derive MyClass from LLInitClass<MyClass> (the Curiously Recurring Template
+ * Pattern) to ensure that the static method MyClass::initClass() will be
+ * called (along with all other LLInitClass<T> subclass initClass() methods)
+ * when someone calls LLInitClassList::instance().fireCallbacks(). This gives
+ * the application specific control over the timing of all such
+ * initializations, without having to insert calls for every such class into
+ * generic application code.
+ */
+template<typename T>
+class LLInitClass
+{
+public:
+	LLInitClass() { sRegister.reference(); }
+
+	// When this static member is initialized, the subclass initClass() method
+	// is registered on LLInitClassList. See sRegister definition below.
+	static LLRegisterWith<LLInitClassList> sRegister;
+};
+
+/**
+ * Derive MyClass from LLDestroyClass<MyClass> (the Curiously Recurring
+ * Template Pattern) to ensure that the static method MyClass::destroyClass()
+ * will be called (along with other LLDestroyClass<T> subclass destroyClass()
+ * methods) when someone calls LLDestroyClassList::instance().fireCallbacks().
+ * This gives the application specific control over the timing of all such
+ * cleanup calls, without having to insert calls for every such class into
+ * generic application code.
+ */
+template<typename T>
+class LLDestroyClass
+{
+public:
+	LLDestroyClass() { sRegister.reference(); }
+
+	// When this static member is initialized, the subclass destroyClass()
+	// method is registered on LLInitClassList. See sRegister definition
+	// below.
+	static LLRegisterWith<LLDestroyClassList> sRegister;
+};
+
+// Here's where LLInitClass<T> specifies the subclass initClass() method.
+template <typename T>
+LLRegisterWith<LLInitClassList>
+LLInitClass<T>::sRegister(std::string(typeid(T).name()) + "::initClass",
+						  &T::initClass);
+// Here's where LLDestroyClass<T> specifies the subclass destroyClass() method.
+template <typename T>
+LLRegisterWith<LLDestroyClassList>
+LLDestroyClass<T>::sRegister(std::string(typeid(T).name()) + "::destroyClass",
+							 &T::destroyClass);
+
+#endif /* ! defined(LL_LLINITDESTROYCLASS_H) */
diff --git a/indra/llcommon/llinitparam.cpp b/indra/llcommon/llinitparam.cpp
index aa2f4eb289..1d104cf55d 100644
--- a/indra/llcommon/llinitparam.cpp
+++ b/indra/llcommon/llinitparam.cpp
@@ -193,7 +193,12 @@ namespace LLInitParam
 		{
 			if (!silent)
 			{
-				p.parserWarning(llformat("Failed to parse parameter \"%s\"", p.getCurrentElementName().c_str()));
+				std::string file_name = p.getCurrentFileName();
+				if(!file_name.empty())
+				{
+					file_name = "in file: " + file_name;
+				}
+				p.parserWarning(llformat("Failed to parse parameter \"%s\" %s", p.getCurrentElementName().c_str(), file_name.c_str()));
 			}
 			return false;
 		}
diff --git a/indra/llcommon/llinitparam.h b/indra/llcommon/llinitparam.h
index c65b05f610..f1f4226c40 100644
--- a/indra/llcommon/llinitparam.h
+++ b/indra/llcommon/llinitparam.h
@@ -551,6 +551,7 @@ namespace LLInitParam
 		}
 
 		virtual std::string getCurrentElementName() = 0;
+		virtual std::string getCurrentFileName() = 0;
 		virtual void parserWarning(const std::string& message);
 		virtual void parserError(const std::string& message);
 		void setParseSilently(bool silent) { mParseSilently = silent; }
diff --git a/indra/llcommon/llleap.cpp b/indra/llcommon/llleap.cpp
index 84d2a12f65..c87d2a3e58 100644
--- a/indra/llcommon/llleap.cpp
+++ b/indra/llcommon/llleap.cpp
@@ -33,6 +33,7 @@
 #include "lltimer.h"
 #include "lluuid.h"
 #include "llleaplistener.h"
+#include "llexception.h"
 
 #if LL_MSVC
 #pragma warning (disable : 4355) // 'this' used in initializer list: yes, intentionally
@@ -69,7 +70,7 @@ public:
         // Rule out empty vector
         if (plugin.empty())
         {
-            throw Error("no plugin command");
+            LLTHROW(Error("no plugin command"));
         }
 
         // Don't leave desc empty either, but in this case, if we weren't
@@ -112,7 +113,7 @@ public:
         // If that didn't work, no point in keeping this LLLeap object.
         if (! mChild)
         {
-            throw Error(STRINGIZE("failed to run " << mDesc));
+            LLTHROW(Error(STRINGIZE("failed to run " << mDesc)));
         }
 
         // Okay, launch apparently worked. Change our mDonePump listener.
diff --git a/indra/llcommon/llleap.h b/indra/llcommon/llleap.h
index e33f25e530..8aac8a64c5 100644
--- a/indra/llcommon/llleap.h
+++ b/indra/llcommon/llleap.h
@@ -13,9 +13,9 @@
 #define LL_LLLEAP_H
 
 #include "llinstancetracker.h"
+#include "llexception.h"
 #include <string>
 #include <vector>
-#include <stdexcept>
 
 /**
  * LLSD Event API Plugin class. Because instances are managed by
@@ -67,9 +67,9 @@ public:
      * string(s) passed to create() might come from an external source. This
      * way the caller can catch LLLeap::Error and try to recover.
      */
-    struct Error: public std::runtime_error
+    struct Error: public LLException
     {
-        Error(const std::string& what): std::runtime_error(what) {}
+        Error(const std::string& what): LLException(what) {}
     };
 
     virtual ~LLLeap();
diff --git a/indra/llcommon/llmake.h b/indra/llcommon/llmake.h
index 9a662a0640..08744f90fb 100644
--- a/indra/llcommon/llmake.h
+++ b/indra/llcommon/llmake.h
@@ -12,12 +12,10 @@
  * 
  *         also relevant:
  *
- *         Template parameter deduction for constructors
- *         http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/p0091r0.html
- *
- *         https://github.com/viboes/std-make
- *
- *         but obviously we're not there yet.
+ *         Template argument deduction for class templates
+ *         http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0091r3.html
+ *         was apparently adopted in June 2016? Unclear when compilers will
+ *         portably support this, but there is hope.
  *
  * $LicenseInfo:firstyear=2015&license=viewerlgpl$
  * Copyright (c) 2015, Linden Research, Inc.
diff --git a/indra/llcommon/llmemory.cpp b/indra/llcommon/llmemory.cpp
index 3a8eabac09..1e04044269 100644
--- a/indra/llcommon/llmemory.cpp
+++ b/indra/llcommon/llmemory.cpp
@@ -591,7 +591,7 @@ char* LLPrivateMemoryPool::LLMemoryBlock::allocate()
 void  LLPrivateMemoryPool::LLMemoryBlock::freeMem(void* addr) 
 {
 	//bit index
-	U32 idx = ((U32)addr - (U32)mBuffer - mDummySize) / mSlotSize ;
+	uintptr_t idx = ((uintptr_t)addr - (uintptr_t)mBuffer - mDummySize) / mSlotSize ;
 
 	U32* bits = &mUsageBits ;
 	if(idx >= 32)
@@ -773,7 +773,7 @@ char* LLPrivateMemoryPool::LLMemoryChunk::allocate(U32 size)
 
 void LLPrivateMemoryPool::LLMemoryChunk::freeMem(void* addr)
 {	
-	U32 blk_idx = getPageIndex((U32)addr) ;
+	U32 blk_idx = getPageIndex((uintptr_t)addr) ;
 	LLMemoryBlock* blk = (LLMemoryBlock*)(mMetaBuffer + blk_idx * sizeof(LLMemoryBlock)) ;
 	blk = blk->mSelf ;
 
@@ -798,7 +798,7 @@ bool LLPrivateMemoryPool::LLMemoryChunk::empty()
 
 bool LLPrivateMemoryPool::LLMemoryChunk::containsAddress(const char* addr) const
 {
-	return (U32)mBuffer <= (U32)addr && (U32)mBuffer + mBufferSize > (U32)addr ;
+	return (uintptr_t)mBuffer <= (uintptr_t)addr && (uintptr_t)mBuffer + mBufferSize > (uintptr_t)addr ;
 }
 
 //debug use
@@ -831,13 +831,13 @@ void LLPrivateMemoryPool::LLMemoryChunk::dump()
 	for(U32 i = 1 ; i < blk_list.size(); i++)
 	{
 		total_size += blk_list[i]->getBufferSize() ;
-		if((U32)blk_list[i]->getBuffer() < (U32)blk_list[i-1]->getBuffer() + blk_list[i-1]->getBufferSize())
+		if((uintptr_t)blk_list[i]->getBuffer() < (uintptr_t)blk_list[i-1]->getBuffer() + blk_list[i-1]->getBufferSize())
 		{
 			LL_ERRS() << "buffer corrupted." << LL_ENDL ;
 		}
 	}
 
-	llassert_always(total_size + mMinBlockSize >= mBufferSize - ((U32)mDataBuffer - (U32)mBuffer)) ;
+	llassert_always(total_size + mMinBlockSize >= mBufferSize - ((uintptr_t)mDataBuffer - (uintptr_t)mBuffer)) ;
 
 	U32 blk_num = (mBufferSize - (mDataBuffer - mBuffer)) / mMinBlockSize ;
 	for(U32 i = 0 ; i < blk_num ; )
@@ -860,7 +860,7 @@ void LLPrivateMemoryPool::LLMemoryChunk::dump()
 #endif
 #if 0
 	LL_INFOS() << "---------------------------" << LL_ENDL ;
-	LL_INFOS() << "Chunk buffer: " << (U32)getBuffer() << " size: " << getBufferSize() << LL_ENDL ;
+	LL_INFOS() << "Chunk buffer: " << (uintptr_t)getBuffer() << " size: " << getBufferSize() << LL_ENDL ;
 
 	LL_INFOS() << "available blocks ... " << LL_ENDL ;
 	for(S32 i = 0 ; i < mBlockLevels ; i++)
@@ -868,7 +868,7 @@ void LLPrivateMemoryPool::LLMemoryChunk::dump()
 		LLMemoryBlock* blk = mAvailBlockList[i] ;
 		while(blk)
 		{
-			LL_INFOS() << "blk buffer " << (U32)blk->getBuffer() << " size: " << blk->getBufferSize() << LL_ENDL ;
+			LL_INFOS() << "blk buffer " << (uintptr_t)blk->getBuffer() << " size: " << blk->getBufferSize() << LL_ENDL ;
 			blk = blk->mNext ;
 		}
 	}
@@ -879,7 +879,7 @@ void LLPrivateMemoryPool::LLMemoryChunk::dump()
 		LLMemoryBlock* blk = mFreeSpaceList[i] ;
 		while(blk)
 		{
-			LL_INFOS() << "blk buffer " << (U32)blk->getBuffer() << " size: " << blk->getBufferSize() << LL_ENDL ;
+			LL_INFOS() << "blk buffer " << (uintptr_t)blk->getBuffer() << " size: " << blk->getBufferSize() << LL_ENDL ;
 			blk = blk->mNext ;
 		}
 	}
@@ -1155,9 +1155,9 @@ void LLPrivateMemoryPool::LLMemoryChunk::addToAvailBlockList(LLMemoryBlock* blk)
 	return ;
 }
 
-U32 LLPrivateMemoryPool::LLMemoryChunk::getPageIndex(U32 addr)
+U32 LLPrivateMemoryPool::LLMemoryChunk::getPageIndex(uintptr_t addr)
 {
-	return (addr - (U32)mDataBuffer) / mMinBlockSize ;
+	return (addr - (uintptr_t)mDataBuffer) / mMinBlockSize ;
 }
 
 //for mAvailBlockList
@@ -1495,7 +1495,7 @@ void LLPrivateMemoryPool::removeChunk(LLMemoryChunk* chunk)
 
 U16 LLPrivateMemoryPool::findHashKey(const char* addr)
 {
-	return (((U32)addr) / CHUNK_SIZE) % mHashFactor ;
+	return (((uintptr_t)addr) / CHUNK_SIZE) % mHashFactor ;
 }
 
 LLPrivateMemoryPool::LLMemoryChunk* LLPrivateMemoryPool::findChunk(const char* addr)
@@ -1720,7 +1720,7 @@ LLPrivateMemoryPoolManager::~LLPrivateMemoryPoolManager()
 		S32 k = 0 ;
 		for(mem_allocation_info_t::iterator iter = sMemAllocationTracker.begin() ; iter != sMemAllocationTracker.end() ; ++iter)
 		{
-			LL_INFOS() << k++ << ", " << (U32)iter->first << " : " << iter->second << LL_ENDL ;
+			LL_INFOS() << k++ << ", " << (uintptr_t)iter->first << " : " << iter->second << LL_ENDL ;
 		}
 		sMemAllocationTracker.clear() ;
 	}
diff --git a/indra/llcommon/llmemory.h b/indra/llcommon/llmemory.h
index 0fb257aab1..5a3c9bd762 100644
--- a/indra/llcommon/llmemory.h
+++ b/indra/llcommon/llmemory.h
@@ -110,11 +110,15 @@ template <typename T> T* LL_NEXT_ALIGNED_ADDRESS_64(T* address)
 	#if defined(LL_WINDOWS)
 		return _aligned_malloc(size, align);
 	#else
+        char* aligned = NULL;
 		void* mem = malloc( size + (align - 1) + sizeof(void*) );
-		char* aligned = ((char*)mem) + sizeof(void*);
-		aligned += align - ((uintptr_t)aligned & (align - 1));
+        if (mem)
+        {
+            aligned = ((char*)mem) + sizeof(void*);
+            aligned += align - ((uintptr_t)aligned & (align - 1));
 
-		((void**)aligned)[-1] = mem;
+            ((void**)aligned)[-1] = mem;
+        }
 		return aligned;
 	#endif
 	}
@@ -134,7 +138,6 @@ template <typename T> T* LL_NEXT_ALIGNED_ADDRESS_64(T* address)
 //------------------------------------------------------------------------------------------------
 //------------------------------------------------------------------------------------------------
 
-#if !LL_USE_TCMALLOC
 inline void* ll_aligned_malloc_16(size_t size) // returned hunk MUST be freed with ll_aligned_free_16().
 {
 #if defined(LL_WINDOWS)
@@ -183,13 +186,6 @@ inline void* ll_aligned_realloc_16(void* ptr, size_t size, size_t old_size) // r
 #endif
 }
 
-#else // USE_TCMALLOC
-// ll_aligned_foo_16 are not needed with tcmalloc
-#define ll_aligned_malloc_16 malloc
-#define ll_aligned_realloc_16(a,b,c) realloc(a,b)
-#define ll_aligned_free_16 free
-#endif // USE_TCMALLOC
-
 inline void* ll_aligned_malloc_32(size_t size) // returned hunk MUST be freed with ll_aligned_free_32().
 {
 #if defined(LL_WINDOWS)
@@ -419,7 +415,7 @@ public:
 		{
 			bool operator()(const LLMemoryBlock* const& lhs, const LLMemoryBlock* const& rhs)
 			{
-				return (U32)lhs->getBuffer() < (U32)rhs->getBuffer();
+				return (uintptr_t)lhs->getBuffer() < (uintptr_t)rhs->getBuffer();
 			}
 		};
 	};
@@ -450,7 +446,7 @@ public:
 		void dump() ;
 
 	private:
-		U32 getPageIndex(U32 addr) ;
+		U32 getPageIndex(uintptr_t addr) ;
 		U32 getBlockLevel(U32 size) ;
 		U16 getPageLevel(U32 size) ;
 		LLMemoryBlock* addBlock(U32 blk_idx) ;
diff --git a/indra/llcommon/llmetricperformancetester.cpp b/indra/llcommon/llmetricperformancetester.cpp
index 1fc821d9a9..16fc365da1 100644
--- a/indra/llcommon/llmetricperformancetester.cpp
+++ b/indra/llcommon/llmetricperformancetester.cpp
@@ -40,7 +40,7 @@
 LLMetricPerformanceTesterBasic::name_tester_map_t LLMetricPerformanceTesterBasic::sTesterMap ;
 
 /*static*/ 
-void LLMetricPerformanceTesterBasic::cleanClass() 
+void LLMetricPerformanceTesterBasic::cleanupClass() 
 {
 	for (name_tester_map_t::iterator iter = sTesterMap.begin() ; iter != sTesterMap.end() ; ++iter)
 	{
diff --git a/indra/llcommon/llmetricperformancetester.h b/indra/llcommon/llmetricperformancetester.h
index 1a18cdf36f..e6b46be1cf 100644
--- a/indra/llcommon/llmetricperformancetester.h
+++ b/indra/llcommon/llmetricperformancetester.h
@@ -156,7 +156,7 @@ public:
 	/**
 	 * @brief Delete all testers and reset the tester map
 	 */
-	static void cleanClass() ;
+	static void cleanupClass() ;
 
 private:
 	// Add a tester to the map. Returns false if adding fails.
diff --git a/indra/llcommon/llpounceable.h b/indra/llcommon/llpounceable.h
new file mode 100644
index 0000000000..0421ce966a
--- /dev/null
+++ b/indra/llcommon/llpounceable.h
@@ -0,0 +1,216 @@
+/**
+ * @file   llpounceable.h
+ * @author Nat Goodspeed
+ * @date   2015-05-22
+ * @brief  LLPounceable is tangentially related to a future: it's a holder for
+ *         a value that may or may not exist yet. Unlike a future, though,
+ *         LLPounceable freely allows reading the held value. (If the held
+ *         type T does not have a distinguished "empty" value, consider using
+ *         LLPounceable<boost::optional<T>>.)
+ *
+ *         LLPounceable::callWhenReady() is this template's claim to fame. It
+ *         allows its caller to "pounce" on the held value as soon as it
+ *         becomes non-empty. Call callWhenReady() with any C++ callable
+ *         accepting T. If the held value is already non-empty, callWhenReady()
+ *         will immediately call the callable with the held value. If the held
+ *         value is empty, though, callWhenReady() will enqueue the callable
+ *         for later. As soon as LLPounceable is assigned a non-empty held
+ *         value, it will flush the queue of deferred callables.
+ *
+ *         Consider a global LLMessageSystem* gMessageSystem. Message system
+ *         initialization happens at a very specific point during viewer
+ *         initialization. Other subsystems want to register callbacks on the
+ *         LLMessageSystem instance as soon as it's initialized, but their own
+ *         initialization may precede that. If we define gMessageSystem to be
+ *         an LLPounceable<LLMessageSystem*>, a subsystem can use
+ *         callWhenReady() to either register immediately (if gMessageSystem
+ *         is already up and runnning) or register as soon as gMessageSystem
+ *         is set with a new, initialized instance.
+ *
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+#if ! defined(LL_LLPOUNCEABLE_H)
+#define LL_LLPOUNCEABLE_H
+
+#include "llsingleton.h"
+#include <boost/noncopyable.hpp>
+#include <boost/call_traits.hpp>
+#include <boost/type_traits/remove_pointer.hpp>
+#include <boost/utility/value_init.hpp>
+#include <boost/unordered_map.hpp>
+#include <boost/signals2/signal.hpp>
+
+// Forward declare the user template, since we want to be able to point to it
+// in some of its implementation classes.
+template <typename T, class TAG>
+class LLPounceable;
+
+template <typename T, typename TAG>
+struct LLPounceableTraits
+{
+    // Our "queue" is a signal object with correct signature.
+    typedef boost::signals2::signal<void (typename boost::call_traits<T>::param_type)> signal_t;
+    // Call callWhenReady() with any callable accepting T.
+    typedef typename signal_t::slot_type func_t;
+    // owner pointer type
+    typedef LLPounceable<T, TAG>* owner_ptr;
+};
+
+// Tag types distinguish the two different implementations of LLPounceable's
+// queue.
+struct LLPounceableQueue {};
+struct LLPounceableStatic {};
+
+// generic LLPounceableQueueImpl deliberately omitted: only the above tags are
+// legal
+template <typename T, class TAG>
+class LLPounceableQueueImpl;
+
+// The implementation selected by LLPounceableStatic uses an LLSingleton
+// because we can't count on a data member queue being initialized at the time
+// we start getting callWhenReady() calls. This is that LLSingleton.
+template <typename T>
+class LLPounceableQueueSingleton:
+    public LLSingleton<LLPounceableQueueSingleton<T> >
+{
+    LLSINGLETON_EMPTY_CTOR(LLPounceableQueueSingleton);
+
+    typedef LLPounceableTraits<T, LLPounceableStatic> traits;
+    typedef typename traits::owner_ptr owner_ptr;
+    typedef typename traits::signal_t signal_t;
+
+    // For a given held type T, every LLPounceable<T, LLPounceableStatic>
+    // instance will call on the SAME LLPounceableQueueSingleton instance --
+    // given how class statics work. We must keep a separate queue for each
+    // LLPounceable instance. Use a hash map for that.
+    typedef boost::unordered_map<owner_ptr, signal_t> map_t;
+
+public:
+    // Disambiguate queues belonging to different LLPounceables.
+    signal_t& get(owner_ptr owner)
+    {
+        // operator[] has find-or-create semantics -- just what we want!
+        return mMap[owner];
+    }
+
+private:
+    map_t mMap;
+};
+
+// LLPounceableQueueImpl that uses the above LLSingleton
+template <typename T>
+class LLPounceableQueueImpl<T, LLPounceableStatic>
+{
+public:
+    typedef LLPounceableTraits<T, LLPounceableStatic> traits;
+    typedef typename traits::owner_ptr owner_ptr;
+    typedef typename traits::signal_t signal_t;
+
+    signal_t& get(owner_ptr owner) const
+    {
+        // this Impl contains nothing; it delegates to the Singleton
+        return LLPounceableQueueSingleton<T>::instance().get(owner);
+    }
+};
+
+// The implementation selected by LLPounceableQueue directly contains the
+// queue of interest, suitable for an LLPounceable we can trust to be fully
+// initialized when it starts getting callWhenReady() calls.
+template <typename T>
+class LLPounceableQueueImpl<T, LLPounceableQueue>
+{
+public:
+    typedef LLPounceableTraits<T, LLPounceableQueue> traits;
+    typedef typename traits::owner_ptr owner_ptr;
+    typedef typename traits::signal_t signal_t;
+
+    signal_t& get(owner_ptr)
+    {
+        return mQueue;
+    }
+
+private:
+    signal_t mQueue;
+};
+
+// LLPounceable<T> is for an LLPounceable instance on the heap or the stack.
+// LLPounceable<T, LLPounceableStatic> is for a static LLPounceable instance.
+template <typename T, class TAG=LLPounceableQueue>
+class LLPounceable: public boost::noncopyable
+{
+private:
+    typedef LLPounceableTraits<T, TAG> traits;
+    typedef typename traits::owner_ptr owner_ptr;
+    typedef typename traits::signal_t signal_t;
+
+public:
+    typedef typename traits::func_t func_t;
+
+    // By default, both the initial value and the distinguished empty value
+    // are a default-constructed T instance. However you can explicitly
+    // specify each.
+    LLPounceable(typename boost::call_traits<T>::value_type init =boost::value_initialized<T>(),
+                 typename boost::call_traits<T>::param_type empty=boost::value_initialized<T>()):
+        mHeld(init),
+        mEmpty(empty)
+    {}
+
+    // make read access to mHeld as cheap and transparent as possible
+    operator T () const { return mHeld; }
+    typename boost::remove_pointer<T>::type operator*() const { return *mHeld; }
+    typename boost::call_traits<T>::value_type operator->() const { return mHeld; }
+    // uncomment 'explicit' as soon as we allow C++11 compilation
+    /*explicit*/ operator bool() const { return bool(mHeld); }
+    bool operator!() const { return ! mHeld; }
+
+    // support both assignment (dumb ptr idiom) and reset() (smart ptr)
+    void operator=(typename boost::call_traits<T>::param_type value)
+    {
+        reset(value);
+    }
+
+    void reset(typename boost::call_traits<T>::param_type value)
+    {
+        mHeld = value;
+        // If this new value is non-empty, flush anything pending in the queue.
+        if (mHeld != mEmpty)
+        {
+            signal_t& signal(get_signal());
+            signal(mHeld);
+            signal.disconnect_all_slots();
+        }
+    }
+
+    // our claim to fame
+    void callWhenReady(const func_t& func)
+    {
+        if (mHeld != mEmpty)
+        {
+            // If the held value is already non-empty, immediately call func()
+            func(mHeld);
+        }
+        else
+        {
+            // Held value still empty, queue func() for later. By default,
+            // connect() enqueues slots in FIFO order.
+            get_signal().connect(func);
+        }
+    }
+
+private:
+    signal_t& get_signal() { return mQueue.get(this); }
+
+    // Store both the current and the empty value.
+    // MAYBE: Might be useful to delegate to LLPounceableTraits the meaning of
+    // testing for "empty." For some types we want operator!(); for others we
+    // want to compare to a distinguished value.
+    typename boost::call_traits<T>::value_type mHeld, mEmpty;
+    // This might either contain the queue (LLPounceableQueue) or delegate to
+    // an LLSingleton (LLPounceableStatic).
+    LLPounceableQueueImpl<T, TAG> mQueue;
+};
+
+#endif /* ! defined(LL_LLPOUNCEABLE_H) */
diff --git a/indra/llcommon/llpreprocessor.h b/indra/llcommon/llpreprocessor.h
index 2c4bcc91f6..3698d9db44 100644
--- a/indra/llcommon/llpreprocessor.h
+++ b/indra/llcommon/llpreprocessor.h
@@ -138,6 +138,12 @@
 #pragma warning( 3      :  4266 )	// 'function' : no override available for virtual member function from base 'type'; function is hidden
 #pragma warning (disable : 4180)	// qualifier applied to function type has no meaning; ignored
 //#pragma warning( disable : 4284 )	// silly MS warning deep inside their <map> include file
+
+#if ADDRESS_SIZE == 64
+// That one is all over the place for x64 builds.
+#pragma warning( disable : 4267 )   // 'var' : conversion from 'size_t' to 'type', possible loss of data)
+#endif
+
 #pragma warning( disable : 4503 )	// 'decorated name length exceeded, name was truncated'. Does not seem to affect compilation.
 #pragma warning( disable : 4800 )	// 'BOOL' : forcing value to bool 'true' or 'false' (performance warning)
 #pragma warning( disable : 4996 )	// warning: deprecated
diff --git a/indra/llcommon/llprocess.cpp b/indra/llcommon/llprocess.cpp
index 44f56daf2d..8c321d06b9 100644
--- a/indra/llcommon/llprocess.cpp
+++ b/indra/llcommon/llprocess.cpp
@@ -34,6 +34,7 @@
 #include "llapr.h"
 #include "apr_signal.h"
 #include "llevents.h"
+#include "llexception.h"
 
 #include <boost/foreach.hpp>
 #include <boost/bind.hpp>
@@ -472,9 +473,9 @@ private:
 *****************************************************************************/
 /// Need an exception to avoid constructing an invalid LLProcess object, but
 /// internal use only
-struct LLProcessError: public std::runtime_error
+struct LLProcessError: public LLException
 {
-	LLProcessError(const std::string& msg): std::runtime_error(msg) {}
+	LLProcessError(const std::string& msg): LLException(msg) {}
 };
 
 LLProcessPtr LLProcess::create(const LLSDOrParams& params)
@@ -530,8 +531,8 @@ LLProcess::LLProcess(const LLSDOrParams& params):
 
 	if (! params.validateBlock(true))
 	{
-		throw LLProcessError(STRINGIZE("not launched: failed parameter validation\n"
-									   << LLSDNotationStreamer(params)));
+		LLTHROW(LLProcessError(STRINGIZE("not launched: failed parameter validation\n"
+										 << LLSDNotationStreamer(params))));
 	}
 
 	mPostend = params.postend;
@@ -596,10 +597,10 @@ LLProcess::LLProcess(const LLSDOrParams& params):
 		}
 		else
 		{
-			throw LLProcessError(STRINGIZE("For " << params.executable()
-										   << ": unsupported FileParam for " << which
-										   << ": type='" << fparam.type()
-										   << "', name='" << fparam.name() << "'"));
+			LLTHROW(LLProcessError(STRINGIZE("For " << params.executable()
+											 << ": unsupported FileParam for " << which
+											 << ": type='" << fparam.type()
+											 << "', name='" << fparam.name() << "'")));
 		}
 	}
 	// By default, pass APR_NO_PIPE for unspecified slots.
@@ -678,7 +679,7 @@ LLProcess::LLProcess(const LLSDOrParams& params):
 	if (ll_apr_warn_status(apr_proc_create(&mProcess, argv[0], &argv[0], NULL, procattr,
 										   gAPRPoolp)))
 	{
-		throw LLProcessError(STRINGIZE(params << " failed"));
+		LLTHROW(LLProcessError(STRINGIZE(params << " failed")));
 	}
 
 	// arrange to call status_callback()
@@ -1063,7 +1064,7 @@ PIPETYPE& LLProcess::getPipe(FILESLOT slot)
 	PIPETYPE* wp = getPipePtr<PIPETYPE>(error, slot);
 	if (! wp)
 	{
-		throw NoPipe(error);
+		LLTHROW(NoPipe(error));
 	}
 	return *wp;
 }
diff --git a/indra/llcommon/llprocess.h b/indra/llcommon/llprocess.h
index 43ccadc412..bfac4567a5 100644
--- a/indra/llcommon/llprocess.h
+++ b/indra/llcommon/llprocess.h
@@ -30,13 +30,13 @@
 #include "llinitparam.h"
 #include "llsdparam.h"
 #include "llwin32headerslean.h"
+#include "llexception.h"
 #include "apr_thread_proc.h"
 #include <boost/shared_ptr.hpp>
 #include <boost/ptr_container/ptr_vector.hpp>
 #include <boost/optional.hpp>
 #include <boost/noncopyable.hpp>
 #include <iosfwd>                   // std::ostream
-#include <stdexcept>
 
 #if LL_WINDOWS
 #include "llwin32headerslean.h"	// for HANDLE
@@ -479,9 +479,9 @@ public:
 
 	/// Exception thrown by getWritePipe(), getReadPipe() if you didn't ask to
 	/// create a pipe at the corresponding FILESLOT.
-	struct NoPipe: public std::runtime_error
+	struct NoPipe: public LLException
 	{
-		NoPipe(const std::string& what): std::runtime_error(what) {}
+		NoPipe(const std::string& what): LLException(what) {}
 	};
 
 	/**
diff --git a/indra/llcommon/llprocessor.cpp b/indra/llcommon/llprocessor.cpp
index e3e1d0c391..65b4507e2d 100644
--- a/indra/llcommon/llprocessor.cpp
+++ b/indra/llcommon/llprocessor.cpp
@@ -398,7 +398,7 @@ static F64 calculate_cpu_frequency(U32 measure_msecs)
 	HANDLE hThread = GetCurrentThread();
 	unsigned long dwCurPriorityClass = GetPriorityClass(hProcess);
 	int iCurThreadPriority = GetThreadPriority(hThread);
-	unsigned long dwProcessMask, dwSystemMask, dwNewMask = 1;
+	DWORD_PTR dwProcessMask, dwSystemMask, dwNewMask = 1;
 	GetProcessAffinityMask(hProcess, &dwProcessMask, &dwSystemMask);
 
 	SetPriorityClass(hProcess, REALTIME_PRIORITY_CLASS);
diff --git a/indra/llcommon/llregistry.h b/indra/llcommon/llregistry.h
index 29950c108d..750fe9fdc8 100644
--- a/indra/llcommon/llregistry.h
+++ b/indra/llcommon/llregistry.h
@@ -247,7 +247,10 @@ class LLRegistrySingleton
 	:	public LLRegistry<KEY, VALUE, COMPARATOR>,
 		public LLSingleton<DERIVED_TYPE>
 {
-	friend class LLSingleton<DERIVED_TYPE>;
+	// This LLRegistrySingleton doesn't use LLSINGLETON(LLRegistrySingleton)
+	// because the concrete class is actually DERIVED_TYPE, not
+	// LLRegistrySingleton. So each concrete subclass needs
+	// LLSINGLETON(whatever) -- not this intermediate base class.
 public:
 	typedef LLRegistry<KEY, VALUE, COMPARATOR>		registry_t;
 	typedef const KEY&								ref_const_key_t;
@@ -269,7 +272,7 @@ public:
 
 		~ScopedRegistrar()
 		{
-			if (!singleton_t::destroyed())
+			if (singleton_t::instanceExists())
 			{
 				popScope();
 			}
diff --git a/indra/llcommon/llsdparam.h b/indra/llcommon/llsdparam.h
index 09f1bdf1e3..93910b70ae 100644
--- a/indra/llcommon/llsdparam.h
+++ b/indra/llcommon/llsdparam.h
@@ -66,6 +66,7 @@ public:
 	}
 
 	/*virtual*/ std::string getCurrentElementName();
+	/*virtual*/ std::string getCurrentFileName(){ return LLStringUtil::null; }
 
 private:
 	void writeSDImpl(LLSD& sd, 
diff --git a/indra/llcommon/llsdserialize.cpp b/indra/llcommon/llsdserialize.cpp
index d49ff0feb5..81ba8631c6 100644
--- a/indra/llcommon/llsdserialize.cpp
+++ b/indra/llcommon/llsdserialize.cpp
@@ -1200,6 +1200,7 @@ bool LLSDBinaryParser::parseString(
 	read(istr, (char*)&value_nbo, sizeof(U32));		 /*Flawfinder: ignore*/
 	S32 size = (S32)ntohl(value_nbo);
 	if(mCheckLimits && (size > mMaxBytesLeft)) return false;
+	if(size < 0) return false;
 	std::vector<char> buf;
 	if(size)
 	{
diff --git a/indra/llcommon/llsingleton.cpp b/indra/llcommon/llsingleton.cpp
index 9b49e52377..9025e53bb2 100644
--- a/indra/llcommon/llsingleton.cpp
+++ b/indra/llcommon/llsingleton.cpp
@@ -25,7 +25,445 @@
  */
 
 #include "linden_common.h"
-
 #include "llsingleton.h"
 
+#include "llerror.h"
+#include "llerrorcontrol.h"         // LLError::is_available()
+#include "lldependencies.h"
+#include "llcoro_get_id.h"
+#include <boost/foreach.hpp>
+#include <boost/unordered_map.hpp>
+#include <algorithm>
+#include <iostream>                 // std::cerr in dire emergency
+#include <sstream>
+#include <stdexcept>
+
+namespace {
+void log(LLError::ELevel level,
+         const char* p1, const char* p2, const char* p3, const char* p4);
+
+void logdebugs(const char* p1="", const char* p2="", const char* p3="", const char* p4="");
+
+bool oktolog();
+} // anonymous namespace
+
+// Our master list of all LLSingletons is itself an LLSingleton. We used to
+// store it in a function-local static, but that could get destroyed before
+// the last of the LLSingletons -- and ~LLSingletonBase() definitely wants to
+// remove itself from the master list. Since the whole point of this master
+// list is to help track inter-LLSingleton dependencies, and since we have
+// this implicit dependency from every LLSingleton to the master list, make it
+// an LLSingleton.
+class LLSingletonBase::MasterList:
+    public LLSingleton<LLSingletonBase::MasterList>
+{
+    LLSINGLETON_EMPTY_CTOR(MasterList);
+
+public:
+    // No need to make this private with accessors; nobody outside this source
+    // file can see it.
+
+    // This is the master list of all instantiated LLSingletons (save the
+    // MasterList itself) in arbitrary order. You MUST call dep_sort() before
+    // traversing this list.
+    LLSingletonBase::list_t mMaster;
+
+    // We need to maintain a stack of LLSingletons currently being
+    // initialized, either in the constructor or in initSingleton(). However,
+    // managing that as a stack depends on having a DISTINCT 'initializing'
+    // stack for every C++ stack in the process! And we have a distinct C++
+    // stack for every running coroutine. It would be interesting and cool to
+    // implement a generic coroutine-local-storage mechanism and use that
+    // here. The trouble is that LLCoros is itself an LLSingleton, so
+    // depending on LLCoros functionality could dig us into infinite
+    // recursion. (Moreover, when we reimplement LLCoros on top of
+    // Boost.Fiber, that library already provides fiber_specific_ptr -- so
+    // it's not worth a great deal of time and energy implementing a generic
+    // equivalent on top of boost::dcoroutine, which is on its way out.)
+    // Instead, use a map of llcoro::id to select the appropriate
+    // coro-specific 'initializing' stack. llcoro::get_id() is carefully
+    // implemented to avoid requiring LLCoros.
+    typedef boost::unordered_map<llcoro::id, LLSingletonBase::list_t> InitializingMap;
+    InitializingMap mInitializing;
+
+    // non-static method, cf. LLSingletonBase::get_initializing()
+    list_t& get_initializing_()
+    {
+        // map::operator[] has find-or-create semantics, exactly what we need
+        // here. It returns a reference to the selected mapped_type instance.
+        return mInitializing[llcoro::get_id()];
+    }
+
+    void cleanup_initializing_()
+    {
+        InitializingMap::iterator found = mInitializing.find(llcoro::get_id());
+        if (found != mInitializing.end())
+        {
+            mInitializing.erase(found);
+        }
+    }
+};
+
+//static
+LLSingletonBase::list_t& LLSingletonBase::get_master()
+{
+    return LLSingletonBase::MasterList::instance().mMaster;
+}
+
+void LLSingletonBase::add_master()
+{
+    // As each new LLSingleton is constructed, add to the master list.
+    get_master().push_back(this);
+}
+
+void LLSingletonBase::remove_master()
+{
+    // When an LLSingleton is destroyed, remove from master list.
+    // add_master() used to capture the iterator to the newly-added list item
+    // so we could directly erase() it from the master list. Unfortunately
+    // that runs afoul of destruction-dependency order problems. So search the
+    // master list, and remove this item IF FOUND. We have few enough
+    // LLSingletons, and they are so rarely destroyed (once per run), that the
+    // cost of a linear search should not be an issue.
+    get_master().remove(this);
+}
+
+//static
+LLSingletonBase::list_t& LLSingletonBase::get_initializing()
+{
+    return LLSingletonBase::MasterList::instance().get_initializing_();
+}
+
+//static
+LLSingletonBase::list_t& LLSingletonBase::get_initializing_from(MasterList* master)
+{
+    return master->get_initializing_();
+}
+
+LLSingletonBase::~LLSingletonBase() {}
+
+void LLSingletonBase::push_initializing(const char* name)
+{
+    // log BEFORE pushing so logging singletons don't cry circularity
+    log_initializing("Pushing", name);
+    get_initializing().push_back(this);
+}
+
+void LLSingletonBase::pop_initializing()
+{
+    list_t& list(get_initializing());
+
+    if (list.empty())
+    {
+        logerrs("Underflow in stack of currently-initializing LLSingletons at ",
+                demangle(typeid(*this).name()).c_str(), "::getInstance()");
+    }
+
+    // Now we know list.back() exists: capture it
+    LLSingletonBase* back(list.back());
+    // and pop it
+    list.pop_back();
+
+    // The viewer launches an open-ended number of coroutines. While we don't
+    // expect most of them to initialize LLSingleton instances, our present
+    // get_initializing() logic could lead to an open-ended number of map
+    // entries. So every time we pop the stack back to empty, delete the entry
+    // entirely.
+    if (list.empty())
+    {
+        MasterList::instance().cleanup_initializing_();
+    }
+
+    // Now validate the newly-popped LLSingleton.
+    if (back != this)
+    {
+        logerrs("Push/pop mismatch in stack of currently-initializing LLSingletons: ",
+                demangle(typeid(*this).name()).c_str(), "::getInstance() trying to pop ",
+                demangle(typeid(*back).name()).c_str());
+    }
+
+    // log AFTER popping so logging singletons don't cry circularity
+    log_initializing("Popping", typeid(*back).name());
+}
+
+//static
+void LLSingletonBase::log_initializing(const char* verb, const char* name)
+{
+    if (oktolog())
+    {
+        LL_DEBUGS("LLSingleton") << verb << ' ' << demangle(name) << ';';
+        list_t& list(get_initializing());
+        for (list_t::const_reverse_iterator ri(list.rbegin()), rend(list.rend());
+             ri != rend; ++ri)
+        {
+            LLSingletonBase* sb(*ri);
+            LL_CONT << ' ' << demangle(typeid(*sb).name());
+        }
+        LL_ENDL;
+    }
+}
+
+void LLSingletonBase::capture_dependency(list_t& initializing, EInitState initState)
+{
+    // Did this getInstance() call come from another LLSingleton, or from
+    // vanilla application code? Note that although this is a nontrivial
+    // method, the vast majority of its calls arrive here with initializing
+    // empty().
+    if (! initializing.empty())
+    {
+        // getInstance() is being called by some other LLSingleton. But -- is
+        // this a circularity? That is, does 'this' already appear in the
+        // initializing stack?
+        // For what it's worth, normally 'initializing' should contain very
+        // few elements.
+        list_t::const_iterator found =
+            std::find(initializing.begin(), initializing.end(), this);
+        if (found != initializing.end())
+        {
+            // Report the circularity. Requiring the coder to dig through the
+            // logic to diagnose exactly how we got here is less than helpful.
+            std::ostringstream out;
+            for ( ; found != initializing.end(); ++found)
+            {
+                // 'found' is an iterator; *found is an LLSingletonBase*; **found
+                // is the actual LLSingletonBase instance.
+                LLSingletonBase* foundp(*found);
+                out << demangle(typeid(*foundp).name()) << " -> ";
+            }
+            // We promise to capture dependencies from both the constructor
+            // and the initSingleton() method, so an LLSingleton's instance
+            // pointer is on the initializing list during both. Now that we've
+            // detected circularity, though, we must distinguish the two. If
+            // the recursive call is from the constructor, we CAN'T honor it:
+            // otherwise we'd be returning a pointer to a partially-
+            // constructed object! But from initSingleton() is okay: that
+            // method exists specifically to support circularity.
+            // Decide which log helper to call based on initState. They have
+            // identical signatures.
+            ((initState == CONSTRUCTING)? logerrs : logwarns)
+                ("LLSingleton circularity: ", out.str().c_str(),
+                 demangle(typeid(*this).name()).c_str(), "");
+        }
+        else
+        {
+            // Here 'this' is NOT already in the 'initializing' stack. Great!
+            // Record the dependency.
+            // initializing.back() is the LLSingletonBase* currently being
+            // initialized. Store 'this' in its mDepends set.
+            LLSingletonBase* current(initializing.back());
+            if (current->mDepends.insert(this).second)
+            {
+                // only log the FIRST time we hit this dependency!
+                logdebugs(demangle(typeid(*current).name()).c_str(),
+                          " depends on ", demangle(typeid(*this).name()).c_str());
+            }
+        }
+    }
+}
+
+//static
+LLSingletonBase::vec_t LLSingletonBase::dep_sort()
+{
+    // While it would theoretically be possible to maintain a static
+    // SingletonDeps through the life of the program, dynamically adding and
+    // removing LLSingletons as they are created and destroyed, in practice
+    // it's less messy to construct it on demand. The overhead of doing so
+    // should happen basically twice: once for cleanupAll(), once for
+    // deleteAll().
+    typedef LLDependencies<LLSingletonBase*> SingletonDeps;
+    SingletonDeps sdeps;
+    list_t& master(get_master());
+    BOOST_FOREACH(LLSingletonBase* sp, master)
+    {
+        // Build the SingletonDeps structure by adding, for each
+        // LLSingletonBase* sp in the master list, sp itself. It has no
+        // associated value type in our SingletonDeps, hence the 0. We don't
+        // record the LLSingletons it must follow; rather, we record the ones
+        // it must precede. Copy its mDepends to a KeyList to express that.
+        sdeps.add(sp, 0,
+                  SingletonDeps::KeyList(),
+                  SingletonDeps::KeyList(sp->mDepends.begin(), sp->mDepends.end()));
+    }
+    vec_t ret;
+    ret.reserve(master.size());
+    // We should be able to effect this with a transform_iterator that
+    // extracts just the first (key) element from each sorted_iterator, then
+    // uses vec_t's range constructor... but frankly this is more
+    // straightforward, as long as we remember the above reserve() call!
+    BOOST_FOREACH(SingletonDeps::sorted_iterator::value_type pair, sdeps.sort())
+    {
+        ret.push_back(pair.first);
+    }
+    // The master list is not itself pushed onto the master list. Add it as
+    // the very last entry -- it is the LLSingleton on which ALL others
+    // depend! -- so our caller will process it.
+    ret.push_back(MasterList::getInstance());
+    return ret;
+}
+
+//static
+void LLSingletonBase::cleanupAll()
+{
+    // It's essential to traverse these in dependency order.
+    BOOST_FOREACH(LLSingletonBase* sp, dep_sort())
+    {
+        // Call cleanupSingleton() only if we haven't already done so for this
+        // instance.
+        if (! sp->mCleaned)
+        {
+            sp->mCleaned = true;
+
+            logdebugs("calling ",
+                      demangle(typeid(*sp).name()).c_str(), "::cleanupSingleton()");
+            try
+            {
+                sp->cleanupSingleton();
+            }
+            catch (const std::exception& e)
+            {
+                logwarns("Exception in ", demangle(typeid(*sp).name()).c_str(),
+                         "::cleanupSingleton(): ", e.what());
+            }
+            catch (...)
+            {
+                logwarns("Unknown exception in ", demangle(typeid(*sp).name()).c_str(),
+                         "::cleanupSingleton()");
+            }
+        }
+    }
+}
+
+//static
+void LLSingletonBase::deleteAll()
+{
+    // It's essential to traverse these in dependency order.
+    BOOST_FOREACH(LLSingletonBase* sp, dep_sort())
+    {
+        // Capture the class name first: in case of exception, don't count on
+        // being able to extract it later.
+        const std::string name = demangle(typeid(*sp).name());
+        try
+        {
+            // Call static method through instance function pointer.
+            if (! sp->mDeleteSingleton)
+            {
+                // This Should Not Happen... but carry on.
+                logwarns(name.c_str(), "::mDeleteSingleton not initialized!");
+            }
+            else
+            {
+                // properly initialized: call it.
+                logdebugs("calling ", name.c_str(), "::deleteSingleton()");
+                // From this point on, DO NOT DEREFERENCE sp!
+                sp->mDeleteSingleton();
+            }
+        }
+        catch (const std::exception& e)
+        {
+            logwarns("Exception in ", name.c_str(), "::deleteSingleton(): ", e.what());
+        }
+        catch (...)
+        {
+            logwarns("Unknown exception in ", name.c_str(), "::deleteSingleton()");
+        }
+    }
+}
+
+/*------------------------ Final cleanup management ------------------------*/
+class LLSingletonBase::MasterRefcount
+{
+public:
+    // store a POD int so it will be statically initialized to 0
+    int refcount;
+};
+static LLSingletonBase::MasterRefcount sMasterRefcount;
+
+LLSingletonBase::ref_ptr_t LLSingletonBase::get_master_refcount()
+{
+    // Calling this method constructs a new ref_ptr_t, which implicitly calls
+    // intrusive_ptr_add_ref(MasterRefcount*).
+    return &sMasterRefcount;
+}
+
+void intrusive_ptr_add_ref(LLSingletonBase::MasterRefcount* mrc)
+{
+    // Count outstanding SingletonLifetimeManager instances.
+    ++mrc->refcount;
+}
+
+void intrusive_ptr_release(LLSingletonBase::MasterRefcount* mrc)
+{
+    // Notice when each SingletonLifetimeManager instance is destroyed.
+    if (! --mrc->refcount)
+    {
+        // The last instance was destroyed. Time to kill any remaining
+        // LLSingletons -- but in dependency order.
+        LLSingletonBase::deleteAll();
+    }
+}
+
+/*---------------------------- Logging helpers -----------------------------*/
+namespace {
+bool oktolog()
+{
+    // See comments in log() below.
+    return sMasterRefcount.refcount && LLError::is_available();
+}
+
+void log(LLError::ELevel level,
+         const char* p1, const char* p2, const char* p3, const char* p4)
+{
+    // Check whether we're in the implicit final LLSingletonBase::deleteAll()
+    // call. We've carefully arranged for deleteAll() to be called when the
+    // last SingletonLifetimeManager instance is destroyed -- in other words,
+    // when the last translation unit containing an LLSingleton instance
+    // cleans up static data. That could happen after std::cerr is destroyed!
+    // The is_available() test below ensures that we'll stop logging once
+    // LLError has been cleaned up. If we had a similar portable test for
+    // std::cerr, this would be a good place to use it. As we do not, just
+    // don't log anything during implicit final deleteAll(). Detect that by
+    // the master refcount having gone to zero.
+    if (sMasterRefcount.refcount == 0)
+        return;
+
+    // Check LLError::is_available() because some of LLError's infrastructure
+    // is itself an LLSingleton. If that LLSingleton has not yet been
+    // initialized, trying to log will engage LLSingleton machinery... and
+    // around and around we go.
+    if (LLError::is_available())
+    {
+        LL_VLOGS(level, "LLSingleton") << p1 << p2 << p3 << p4 << LL_ENDL;
+    }
+    else
+    {
+        // Caller may be a test program, or something else whose stderr is
+        // visible to the user.
+        std::cerr << p1 << p2 << p3 << p4 << std::endl;
+    }
+}
+
+void logdebugs(const char* p1, const char* p2, const char* p3, const char* p4)
+{
+    log(LLError::LEVEL_DEBUG, p1, p2, p3, p4);
+}
+} // anonymous namespace        
+
+//static
+void LLSingletonBase::logwarns(const char* p1, const char* p2, const char* p3, const char* p4)
+{
+    log(LLError::LEVEL_WARN, p1, p2, p3, p4);
+}
+
+//static
+void LLSingletonBase::logerrs(const char* p1, const char* p2, const char* p3, const char* p4)
+{
+    log(LLError::LEVEL_ERROR, p1, p2, p3, p4);
+    // The other important side effect of LL_ERRS() is
+    // https://www.youtube.com/watch?v=OMG7paGJqhQ (emphasis on OMG)
+    LLError::crashAndLoop(std::string());
+}
 
+std::string LLSingletonBase::demangle(const char* mangled)
+{
+    return LLError::Log::demangle(mangled);
+}
diff --git a/indra/llcommon/llsingleton.h b/indra/llcommon/llsingleton.h
index 6e6291a165..1b915dfd6e 100644
--- a/indra/llcommon/llsingleton.h
+++ b/indra/llcommon/llsingleton.h
@@ -25,188 +25,495 @@
 #ifndef LLSINGLETON_H
 #define LLSINGLETON_H
 
-#include "llerror.h"	// *TODO: eliminate this
-
-#include <typeinfo>
 #include <boost/noncopyable.hpp>
+#include <boost/unordered_set.hpp>
+#include <boost/intrusive_ptr.hpp>
+#include <list>
+#include <vector>
+#include <typeinfo>
+
+class LLSingletonBase: private boost::noncopyable
+{
+public:
+    class MasterList;
+    class MasterRefcount;
+    typedef boost::intrusive_ptr<MasterRefcount> ref_ptr_t;
+
+private:
+    // All existing LLSingleton instances are tracked in this master list.
+    typedef std::list<LLSingletonBase*> list_t;
+    static list_t& get_master();
+    // This, on the other hand, is a stack whose top indicates the LLSingleton
+    // currently being initialized.
+    static list_t& get_initializing();
+    static list_t& get_initializing_from(MasterList*);
+    // Produce a vector<LLSingletonBase*> of master list, in dependency order.
+    typedef std::vector<LLSingletonBase*> vec_t;
+    static vec_t dep_sort();
+
+    bool mCleaned;                  // cleanupSingleton() has been called
+    // we directly depend on these other LLSingletons
+    typedef boost::unordered_set<LLSingletonBase*> set_t;
+    set_t mDepends;
+
+protected:
+    typedef enum e_init_state
+    {
+        UNINITIALIZED = 0,          // must be default-initialized state
+        CONSTRUCTING,
+        INITIALIZING,
+        INITIALIZED,
+        DELETED
+    } EInitState;
+
+    // Define tag<T> to pass to our template constructor. You can't explicitly
+    // invoke a template constructor with ordinary template syntax:
+    // http://stackoverflow.com/a/3960925/5533635
+    template <typename T>
+    struct tag
+    {
+        typedef T type;
+    };
+
+    // Base-class constructor should only be invoked by the DERIVED_TYPE
+    // constructor, which passes tag<DERIVED_TYPE> for various purposes.
+    template <typename DERIVED_TYPE>
+    LLSingletonBase(tag<DERIVED_TYPE>);
+    virtual ~LLSingletonBase();
+
+    // Every new LLSingleton should be added to/removed from the master list
+    void add_master();
+    void remove_master();
+    // with a little help from our friends.
+    template <class T> friend struct LLSingleton_manage_master;
+
+    // Maintain a stack of the LLSingleton subclass instance currently being
+    // initialized. We use this to notice direct dependencies: we want to know
+    // if A requires B. We deduce a dependency if while initializing A,
+    // control reaches B::getInstance().
+    // We want &A to be at the top of that stack during both A::A() and
+    // A::initSingleton(), since a call to B::getInstance() might occur during
+    // either.
+    // Unfortunately the desired timespan does not correspond neatly with a
+    // single C++ scope, else we'd use RAII to track it. But we do know that
+    // LLSingletonBase's constructor definitely runs just before
+    // LLSingleton's, which runs just before the specific subclass's.
+    void push_initializing(const char*);
+    // LLSingleton is, and must remain, the only caller to initSingleton().
+    // That being the case, we control exactly when it happens -- and we can
+    // pop the stack immediately thereafter.
+    void pop_initializing();
+private:
+    // logging
+    static void log_initializing(const char* verb, const char* name);
+protected:
+    // If a given call to B::getInstance() happens during either A::A() or
+    // A::initSingleton(), record that A directly depends on B.
+    void capture_dependency(list_t& initializing, EInitState);
+
+    // delegate LL_ERRS() logging to llsingleton.cpp
+    static void logerrs(const char* p1, const char* p2="",
+                        const char* p3="", const char* p4="");
+    // delegate LL_WARNS() logging to llsingleton.cpp
+    static void logwarns(const char* p1, const char* p2="",
+                         const char* p3="", const char* p4="");
+    static std::string demangle(const char* mangled);
+
+    // obtain canonical ref_ptr_t
+    static ref_ptr_t get_master_refcount();
+
+    // Default methods in case subclass doesn't declare them.
+    virtual void initSingleton() {}
+    virtual void cleanupSingleton() {}
+
+    // deleteSingleton() isn't -- and shouldn't be -- a virtual method. It's a
+    // class static. However, given only Foo*, deleteAll() does need to be
+    // able to reach Foo::deleteSingleton(). Make LLSingleton (which declares
+    // deleteSingleton()) store a pointer here. Since we know it's a static
+    // class method, a classic-C function pointer will do.
+    void (*mDeleteSingleton)();
+
+public:
+    /**
+     * Call this to call the cleanupSingleton() method for every LLSingleton
+     * constructed since the start of the last cleanupAll() call. (Any
+     * LLSingleton constructed DURING a cleanupAll() call won't be cleaned up
+     * until the next cleanupAll() call.) cleanupSingleton() neither deletes
+     * nor destroys its LLSingleton; therefore it's safe to include logic that
+     * might take significant realtime or even throw an exception.
+     *
+     * The most important property of cleanupAll() is that cleanupSingleton()
+     * methods are called in dependency order, leaf classes last. Thus, given
+     * two LLSingleton subclasses A and B, if A's dependency on B is properly
+     * expressed as a B::getInstance() or B::instance() call during either
+     * A::A() or A::initSingleton(), B will be cleaned up after A.
+     *
+     * If a cleanupSingleton() method throws an exception, the exception is
+     * logged, but cleanupAll() attempts to continue calling the rest of the
+     * cleanupSingleton() methods.
+     */
+    static void cleanupAll();
+    /**
+     * Call this to call the deleteSingleton() method for every LLSingleton
+     * constructed since the start of the last deleteAll() call. (Any
+     * LLSingleton constructed DURING a deleteAll() call won't be cleaned up
+     * until the next deleteAll() call.) deleteSingleton() deletes and
+     * destroys its LLSingleton. Any cleanup logic that might take significant
+     * realtime -- or throw an exception -- must not be placed in your
+     * LLSingleton's destructor, but rather in its cleanupSingleton() method.
+     *
+     * The most important property of deleteAll() is that deleteSingleton()
+     * methods are called in dependency order, leaf classes last. Thus, given
+     * two LLSingleton subclasses A and B, if A's dependency on B is properly
+     * expressed as a B::getInstance() or B::instance() call during either
+     * A::A() or A::initSingleton(), B will be cleaned up after A.
+     *
+     * If a deleteSingleton() method throws an exception, the exception is
+     * logged, but deleteAll() attempts to continue calling the rest of the
+     * deleteSingleton() methods.
+     */
+    static void deleteAll();
+};
+
+// support ref_ptr_t
+void intrusive_ptr_add_ref(LLSingletonBase::MasterRefcount*);
+void intrusive_ptr_release(LLSingletonBase::MasterRefcount*);
 
-// LLSingleton implements the getInstance() method part of the Singleton
-// pattern. It can't make the derived class constructors protected, though, so
-// you have to do that yourself.
-//
-// There are two ways to use LLSingleton. The first way is to inherit from it
-// while using the typename that you'd like to be static as the template
-// parameter, like so:
-//
-//   class Foo: public LLSingleton<Foo>{};
-//
-//   Foo& instance = Foo::instance();
-//
-// The second way is to use the singleton class directly, without inheritance:
-//
-//   typedef LLSingleton<Foo> FooSingleton;
-//
-//   Foo& instance = FooSingleton::instance();
-//
-// In this case, the class being managed as a singleton needs to provide an
-// initSingleton() method since the LLSingleton virtual method won't be
-// available
-//
-// As currently written, it is not thread-safe.
+// Most of the time, we want LLSingleton_manage_master() to forward its
+// methods to real LLSingletonBase methods.
+template <class T>
+struct LLSingleton_manage_master
+{
+    void add(LLSingletonBase* sb) { sb->add_master(); }
+    void remove(LLSingletonBase* sb) { sb->remove_master(); }
+    void push_initializing(LLSingletonBase* sb) { sb->push_initializing(typeid(T).name()); }
+    void pop_initializing (LLSingletonBase* sb) { sb->pop_initializing(); }
+    LLSingletonBase::list_t& get_initializing(T*) { return LLSingletonBase::get_initializing(); }
+};
 
+// But for the specific case of LLSingletonBase::MasterList, don't.
+template <>
+struct LLSingleton_manage_master<LLSingletonBase::MasterList>
+{
+    void add(LLSingletonBase*) {}
+    void remove(LLSingletonBase*) {}
+    void push_initializing(LLSingletonBase*) {}
+    void pop_initializing (LLSingletonBase*) {}
+    LLSingletonBase::list_t& get_initializing(LLSingletonBase::MasterList* instance)
+    {
+        return LLSingletonBase::get_initializing_from(instance);
+    }
+};
+
+// Now we can implement LLSingletonBase's template constructor.
 template <typename DERIVED_TYPE>
-class LLSingleton : private boost::noncopyable
+LLSingletonBase::LLSingletonBase(tag<DERIVED_TYPE>):
+    mCleaned(false),
+    mDeleteSingleton(NULL)
+{
+    // Make this the currently-initializing LLSingleton.
+    LLSingleton_manage_master<DERIVED_TYPE>().push_initializing(this);
+}
+
+/**
+ * LLSingleton implements the getInstance() method part of the Singleton
+ * pattern. It can't make the derived class constructors protected, though, so
+ * you have to do that yourself.
+ *
+ * Derive your class from LLSingleton, passing your subclass name as
+ * LLSingleton's template parameter, like so:
+ *
+ *   class Foo: public LLSingleton<Foo>
+ *   {
+ *       // use this macro at start of every LLSingleton subclass
+ *       LLSINGLETON(Foo);
+ *   public:
+ *       // ...
+ *   };
+ *
+ *   Foo& instance = Foo::instance();
+ *
+ * LLSingleton recognizes a couple special methods in your derived class.
+ *
+ * If you override LLSingleton<T>::initSingleton(), your method will be called
+ * immediately after the instance is constructed. This is useful for breaking
+ * circular dependencies: if you find that your LLSingleton subclass
+ * constructor references other LLSingleton subclass instances in a chain
+ * leading back to yours, move the instance reference from your constructor to
+ * your initSingleton() method.
+ *
+ * If you override LLSingleton<T>::cleanupSingleton(), your method will be
+ * called if someone calls LLSingletonBase::cleanupAll(). The significant part
+ * of this promise is that cleanupAll() will call individual
+ * cleanupSingleton() methods in reverse dependency order.
+ *
+ * That is, consider LLSingleton subclasses C, B and A. A depends on B, which
+ * in turn depends on C. These dependencies are expressed as calls to
+ * B::instance() or B::getInstance(), and C::instance() or C::getInstance().
+ * It shouldn't matter whether these calls appear in A::A() or
+ * A::initSingleton(), likewise B::B() or B::initSingleton().
+ *
+ * We promise that if you later call LLSingletonBase::cleanupAll():
+ * 1. A::cleanupSingleton() will be called before
+ * 2. B::cleanupSingleton(), which will be called before
+ * 3. C::cleanupSingleton().
+ * Put differently, if your LLSingleton subclass constructor or
+ * initSingleton() method explicitly depends on some other LLSingleton
+ * subclass, you may continue to rely on that other subclass in your
+ * cleanupSingleton() method.
+ *
+ * We introduce a special cleanupSingleton() method because cleanupSingleton()
+ * operations can involve nontrivial realtime, or might throw an exception. A
+ * destructor should do neither!
+ *
+ * If your cleanupSingleton() method throws an exception, we log that
+ * exception but proceed with the remaining cleanupSingleton() calls.
+ *
+ * Similarly, if at some point you call LLSingletonBase::deleteAll(), all
+ * remaining LLSingleton instances will be destroyed in dependency order. (Or
+ * call MySubclass::deleteSingleton() to specifically destroy the canonical
+ * MySubclass instance.)
+ *
+ * As currently written, LLSingleton is not thread-safe.
+ */
+template <typename DERIVED_TYPE>
+class LLSingleton : public LLSingletonBase
 {
-	
 private:
-	typedef enum e_init_state
-	{
-		UNINITIALIZED,
-		CONSTRUCTING,
-		INITIALIZING,
-		INITIALIZED,
-		DELETED
-	} EInitState;
-    
     static DERIVED_TYPE* constructSingleton()
     {
         return new DERIVED_TYPE();
     }
-	
-	// stores pointer to singleton instance
-	struct SingletonLifetimeManager
-	{
-		SingletonLifetimeManager()
-		{
-			construct();
-		}
-
-		static void construct()
-		{
-			sData.mInitState = CONSTRUCTING;
-			sData.mInstance = constructSingleton();
-			sData.mInitState = INITIALIZING;
-		}
-
-		~SingletonLifetimeManager()
-		{
-			if (sData.mInitState != DELETED)
-			{
-				deleteSingleton();
-			}
-		}
-	};
-	
+
+    // We know of no way to instruct the compiler that every subclass
+    // constructor MUST be private. However, we can make the LLSINGLETON()
+    // macro both declare a private constructor and provide the required
+    // friend declaration. How can we ensure that every subclass uses
+    // LLSINGLETON()? By making that macro provide a definition for this pure
+    // virtual method. If you get "can't instantiate class due to missing pure
+    // virtual method" for this method, then add LLSINGLETON(yourclass) in the
+    // subclass body.
+    virtual void you_must_use_LLSINGLETON_macro() = 0;
+
+    // stores pointer to singleton instance
+    struct SingletonLifetimeManager
+    {
+        SingletonLifetimeManager():
+            mMasterRefcount(LLSingletonBase::get_master_refcount())
+        {
+            construct();
+        }
+
+        static void construct()
+        {
+            sData.mInitState = CONSTRUCTING;
+            sData.mInstance = constructSingleton();
+            sData.mInitState = INITIALIZING;
+        }
+
+        ~SingletonLifetimeManager()
+        {
+            // The dependencies between LLSingletons, and the arbitrary order
+            // of static-object destruction, mean that we DO NOT WANT this
+            // destructor to delete this LLSingleton. This destructor will run
+            // without regard to any other LLSingleton whose cleanup might
+            // depend on its existence. What we really want is to count the
+            // runtime's attempts to cleanup LLSingleton static data -- and on
+            // the very last one, call LLSingletonBase::deleteAll(). That
+            // method will properly honor cross-LLSingleton dependencies. This
+            // is why we store an intrusive_ptr to a MasterRefcount: our
+            // ref_ptr_t member counts SingletonLifetimeManager instances.
+            // Once the runtime destroys the last of these, THEN we can delete
+            // every remaining LLSingleton.
+        }
+
+        LLSingletonBase::ref_ptr_t mMasterRefcount;
+    };
+
+protected:
+    // Pass DERIVED_TYPE explicitly to LLSingletonBase's constructor because,
+    // until our subclass constructor completes, *this isn't yet a
+    // full-fledged DERIVED_TYPE.
+    LLSingleton(): LLSingletonBase(LLSingletonBase::tag<DERIVED_TYPE>())
+    {
+        // populate base-class function pointer with the static
+        // deleteSingleton() function for this particular specialization
+        mDeleteSingleton = &deleteSingleton;
+
+        // add this new instance to the master list
+        LLSingleton_manage_master<DERIVED_TYPE>().add(this);
+    }
+
 public:
-	virtual ~LLSingleton()
-	{
-		sData.mInstance = NULL;
-		sData.mInitState = DELETED;
-	}
-
-	/**
-	 * @brief Immediately delete the singleton.
-	 *
-	 * A subsequent call to LLProxy::getInstance() will construct a new
-	 * instance of the class.
-	 *
-	 * LLSingletons are normally destroyed after main() has exited and the C++
-	 * runtime is cleaning up statically-constructed objects. Some classes
-	 * derived from LLSingleton have objects that are part of a runtime system
-	 * that is terminated before main() exits. Calling the destructor of those
-	 * objects after the termination of their respective systems can cause
-	 * crashes and other problems during termination of the project. Using this
-	 * method to destroy the singleton early can prevent these crashes.
-	 *
-	 * An example where this is needed is for a LLSingleton that has an APR
-	 * object as a member that makes APR calls on destruction. The APR system is
-	 * shut down explicitly before main() exits. This causes a crash on exit.
-	 * Using this method before the call to apr_terminate() and NOT calling
-	 * getInstance() again will prevent the crash.
-	 */
-	static void deleteSingleton()
-	{
-		delete sData.mInstance;
-		sData.mInstance = NULL;
-		sData.mInitState = DELETED;
-	}
-
-
-	static DERIVED_TYPE* getInstance()
-	{
-		static SingletonLifetimeManager sLifeTimeMgr;
-
-		switch (sData.mInitState)
-		{
-		case UNINITIALIZED:
-			// should never be uninitialized at this point
-			llassert(false);
-			return NULL;
-		case CONSTRUCTING:
-			LL_ERRS() << "Tried to access singleton " << typeid(DERIVED_TYPE).name() << " from singleton constructor!" << LL_ENDL;
-			return NULL;
-		case INITIALIZING:
-			// go ahead and flag ourselves as initialized so we can be reentrant during initialization
-			sData.mInitState = INITIALIZED;	
-			// initialize singleton after constructing it so that it can reference other singletons which in turn depend on it,
-			// thus breaking cyclic dependencies
-			sData.mInstance->initSingleton(); 
-			return sData.mInstance;
-		case INITIALIZED:
-			return sData.mInstance;
-		case DELETED:
-			LL_WARNS() << "Trying to access deleted singleton " << typeid(DERIVED_TYPE).name() << " creating new instance" << LL_ENDL;
-			SingletonLifetimeManager::construct();
-			// same as first time construction
-			sData.mInitState = INITIALIZED;	
-			sData.mInstance->initSingleton(); 
-			return sData.mInstance;
-		}
-
-		return NULL;
-	}
-
-	static DERIVED_TYPE* getIfExists()
-	{
-		return sData.mInstance;
-	}
-
-	// Reference version of getInstance()
-	// Preferred over getInstance() as it disallows checking for NULL
-	static DERIVED_TYPE& instance()
-	{
-		return *getInstance();
-	}
-	
-	// Has this singleton been created uet?
-	// Use this to avoid accessing singletons before the can safely be constructed
-	static bool instanceExists()
-	{
-		return sData.mInitState == INITIALIZED;
-	}
-	
-	// Has this singleton already been deleted?
-	// Use this to avoid accessing singletons from a static object's destructor
-	static bool destroyed()
-	{
-		return sData.mInitState == DELETED;
-	}
+    virtual ~LLSingleton()
+    {
+        // remove this instance from the master list
+        LLSingleton_manage_master<DERIVED_TYPE>().remove(this);
+        sData.mInstance = NULL;
+        sData.mInitState = DELETED;
+    }
 
-private:
+    /**
+     * @brief Immediately delete the singleton.
+     *
+     * A subsequent call to LLProxy::getInstance() will construct a new
+     * instance of the class.
+     *
+     * Without an explicit call to LLSingletonBase::deleteAll(), LLSingletons
+     * are implicitly destroyed after main() has exited and the C++ runtime is
+     * cleaning up statically-constructed objects. Some classes derived from
+     * LLSingleton have objects that are part of a runtime system that is
+     * terminated before main() exits. Calling the destructor of those objects
+     * after the termination of their respective systems can cause crashes and
+     * other problems during termination of the project. Using this method to
+     * destroy the singleton early can prevent these crashes.
+     *
+     * An example where this is needed is for a LLSingleton that has an APR
+     * object as a member that makes APR calls on destruction. The APR system is
+     * shut down explicitly before main() exits. This causes a crash on exit.
+     * Using this method before the call to apr_terminate() and NOT calling
+     * getInstance() again will prevent the crash.
+     */
+    static void deleteSingleton()
+    {
+        delete sData.mInstance;
+        sData.mInstance = NULL;
+        sData.mInitState = DELETED;
+    }
+
+    static DERIVED_TYPE* getInstance()
+    {
+        static SingletonLifetimeManager sLifeTimeMgr;
 
-	virtual void initSingleton() {}
+        switch (sData.mInitState)
+        {
+        case UNINITIALIZED:
+            // should never be uninitialized at this point
+            logerrs("Uninitialized singleton ",
+                    demangle(typeid(DERIVED_TYPE).name()).c_str());
+            return NULL;
 
-	struct SingletonData
-	{
-		// explicitly has a default constructor so that member variables are zero initialized in BSS
-		// and only changed by singleton logic, not constructor running during startup
-		EInitState		mInitState;
-		DERIVED_TYPE*	mInstance;
-	};
-	static SingletonData sData;
+        case CONSTRUCTING:
+            logerrs("Tried to access singleton ",
+                    demangle(typeid(DERIVED_TYPE).name()).c_str(),
+                    " from singleton constructor!");
+            return NULL;
+
+        case INITIALIZING:
+            // go ahead and flag ourselves as initialized so we can be
+            // reentrant during initialization
+            sData.mInitState = INITIALIZED; 
+            // initialize singleton after constructing it so that it can
+            // reference other singletons which in turn depend on it, thus
+            // breaking cyclic dependencies
+            sData.mInstance->initSingleton();
+            // pop this off stack of initializing singletons
+            LLSingleton_manage_master<DERIVED_TYPE>().pop_initializing(sData.mInstance);
+            break;
+
+        case INITIALIZED:
+            break;
+
+        case DELETED:
+            logwarns("Trying to access deleted singleton ",
+                     demangle(typeid(DERIVED_TYPE).name()).c_str(),
+                     " -- creating new instance");
+            SingletonLifetimeManager::construct();
+            // same as first time construction
+            sData.mInitState = INITIALIZED; 
+            sData.mInstance->initSingleton(); 
+            // pop this off stack of initializing singletons
+            LLSingleton_manage_master<DERIVED_TYPE>().pop_initializing(sData.mInstance);
+            break;
+        }
+
+        // By this point, if DERIVED_TYPE was pushed onto the initializing
+        // stack, it has been popped off. So the top of that stack, if any, is
+        // an LLSingleton that directly depends on DERIVED_TYPE. If this call
+        // came from another LLSingleton, rather than from vanilla application
+        // code, record the dependency.
+        sData.mInstance->capture_dependency(
+            LLSingleton_manage_master<DERIVED_TYPE>().get_initializing(sData.mInstance),
+            sData.mInitState);
+        return sData.mInstance;
+    }
+
+    // Reference version of getInstance()
+    // Preferred over getInstance() as it disallows checking for NULL
+    static DERIVED_TYPE& instance()
+    {
+        return *getInstance();
+    }
+
+    // Has this singleton been created yet?
+    // Use this to avoid accessing singletons before they can safely be constructed.
+    static bool instanceExists()
+    {
+        return sData.mInitState == INITIALIZED;
+    }
+
+private:
+    struct SingletonData
+    {
+        // explicitly has a default constructor so that member variables are zero initialized in BSS
+        // and only changed by singleton logic, not constructor running during startup
+        EInitState      mInitState;
+        DERIVED_TYPE*   mInstance;
+    };
+    static SingletonData sData;
 };
 
 template<typename T>
 typename LLSingleton<T>::SingletonData LLSingleton<T>::sData;
 
+/**
+ * Use LLSINGLETON(Foo); at the start of an LLSingleton<Foo> subclass body
+ * when you want to declare an out-of-line constructor:
+ *
+ * @code
+ *   class Foo: public LLSingleton<Foo>
+ *   {
+ *       // use this macro at start of every LLSingleton subclass
+ *       LLSINGLETON(Foo);
+ *   public:
+ *       // ...
+ *   };
+ *   // ...
+ *   [inline]
+ *   Foo::Foo() { ... }
+ * @endcode
+ *
+ * Unfortunately, this mechanism does not permit you to define even a simple
+ * (but nontrivial) constructor within the class body. If it's literally
+ * trivial, use LLSINGLETON_EMPTY_CTOR(); if not, use LLSINGLETON() and define
+ * the constructor outside the class body. If you must define it in a header
+ * file, use 'inline' (unless it's a template class) to avoid duplicate-symbol
+ * errors at link time.
+ */
+#define LLSINGLETON(DERIVED_CLASS)                                      \
+private:                                                                \
+    /* implement LLSingleton pure virtual method whose sole purpose */  \
+    /* is to remind people to use this macro */                         \
+    virtual void you_must_use_LLSINGLETON_macro() {}                    \
+    friend class LLSingleton<DERIVED_CLASS>;                            \
+    DERIVED_CLASS()
+
+/**
+ * Use LLSINGLETON_EMPTY_CTOR(Foo); at the start of an LLSingleton<Foo>
+ * subclass body when the constructor is trivial:
+ *
+ * @code
+ *   class Foo: public LLSingleton<Foo>
+ *   {
+ *       // use this macro at start of every LLSingleton subclass
+ *       LLSINGLETON_EMPTY_CTOR(Foo);
+ *   public:
+ *       // ...
+ *   };
+ * @endcode
+ */
+#define LLSINGLETON_EMPTY_CTOR(DERIVED_CLASS)                           \
+    /* LLSINGLETON() is carefully implemented to permit exactly this */ \
+    LLSINGLETON(DERIVED_CLASS) {}
+
 #endif
diff --git a/indra/llcommon/llstl.h b/indra/llcommon/llstl.h
index 0435cb8a08..b024b47225 100644
--- a/indra/llcommon/llstl.h
+++ b/indra/llcommon/llstl.h
@@ -242,7 +242,6 @@ inline T* get_ptr_in_map(const std::map<K,T*>& inmap, const K& key)
 template <typename K, typename T>
 inline bool is_in_map(const std::map<K,T>& inmap, const K& key)
 {
-	typedef typename std::map<K,T>::const_iterator map_iter;
 	if(inmap.find(key) == inmap.end())
 	{
 		return false;
diff --git a/indra/llcommon/llstring.cpp b/indra/llcommon/llstring.cpp
index f3b8999883..c45db3b185 100644
--- a/indra/llcommon/llstring.cpp
+++ b/indra/llcommon/llstring.cpp
@@ -576,6 +576,33 @@ std::string utf8str_truncate(const std::string& utf8str, const S32 max_len)
 	}
 }
 
+std::string utf8str_symbol_truncate(const std::string& utf8str, const S32 symbol_len)
+{
+    if (0 == symbol_len)
+    {
+        return std::string();
+    }
+    if ((S32)utf8str.length() <= symbol_len)
+    {
+        return utf8str;
+    }
+    else
+    {
+        int len = 0, byteIndex = 0;
+        const char* aStr = utf8str.c_str();
+        size_t origSize = utf8str.size();
+
+        for (byteIndex = 0; len < symbol_len && byteIndex < origSize; byteIndex++)
+        {
+            if ((aStr[byteIndex] & 0xc0) != 0x80)
+            {
+                len += 1;
+            }
+        }
+        return utf8str.substr(0, byteIndex);
+    }
+}
+
 std::string utf8str_substChar(
 	const std::string& utf8str,
 	const llwchar target_char,
diff --git a/indra/llcommon/llstring.h b/indra/llcommon/llstring.h
index 393f6d7a8c..2fdb8be84f 100644
--- a/indra/llcommon/llstring.h
+++ b/indra/llcommon/llstring.h
@@ -443,7 +443,7 @@ public:
 struct LLDictionaryLess
 {
 public:
-	bool operator()(const std::string& a, const std::string& b)
+	bool operator()(const std::string& a, const std::string& b) const
 	{
 		return (LLStringUtil::precedesDict(a, b) ? true : false);
 	}
@@ -564,6 +564,17 @@ LL_COMMON_API S32 utf8str_compare_insensitive(
 	const std::string& rhs);
 
 /**
+* @brief Properly truncate a utf8 string to a maximum character count.
+*
+* If symbol_len is longer than the string passed in, the return
+* value == utf8str.
+* @param utf8str A valid utf8 string to truncate.
+* @param symbol_len The maximum number of symbols in the return value.
+* @return Returns a valid utf8 string with symbol count <= max_len.
+*/
+LL_COMMON_API std::string utf8str_symbol_truncate(const std::string& utf8str, const S32 symbol_len);
+
+/**
  * @brief Replace all occurences of target_char with replace_char
  *
  * @param utf8str A utf8 string to process.
diff --git a/indra/llcommon/llthread.cpp b/indra/llcommon/llthread.cpp
index c3f235c6ee..52255bfaeb 100644
--- a/indra/llcommon/llthread.cpp
+++ b/indra/llcommon/llthread.cpp
@@ -63,7 +63,7 @@ void set_thread_name( DWORD dwThreadID, const char* threadName)
 
 	__try
 	{
-		::RaiseException( MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (DWORD*)&info );
+		::RaiseException( MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (ULONG_PTR*)&info );
 	}
 	__except(EXCEPTION_CONTINUE_EXECUTION)
 	{
diff --git a/indra/llcommon/llthreadsafequeue.cpp b/indra/llcommon/llthreadsafequeue.cpp
index 185f0d63fb..491f920c0f 100644
--- a/indra/llcommon/llthreadsafequeue.cpp
+++ b/indra/llcommon/llthreadsafequeue.cpp
@@ -27,6 +27,7 @@
 #include <apr_pools.h>
 #include <apr_queue.h>
 #include "llthreadsafequeue.h"
+#include "llexception.h"
 
 
 
@@ -41,13 +42,13 @@ LLThreadSafeQueueImplementation::LLThreadSafeQueueImplementation(apr_pool_t * po
 {
 	if(mOwnsPool) {
 		apr_status_t status = apr_pool_create(&mPool, 0);
-		if(status != APR_SUCCESS) throw LLThreadSafeQueueError("failed to allocate pool");
+		if(status != APR_SUCCESS) LLTHROW(LLThreadSafeQueueError("failed to allocate pool"));
 	} else {
 		; // No op.
 	}
 	
 	apr_status_t status = apr_queue_create(&mQueue, capacity, mPool);
-	if(status != APR_SUCCESS) throw LLThreadSafeQueueError("failed to allocate queue");
+	if(status != APR_SUCCESS) LLTHROW(LLThreadSafeQueueError("failed to allocate queue"));
 }
 
 
@@ -68,9 +69,9 @@ void LLThreadSafeQueueImplementation::pushFront(void * element)
 	apr_status_t status = apr_queue_push(mQueue, element);
 	
 	if(status == APR_EINTR) {
-		throw LLThreadSafeQueueInterrupt();
+		LLTHROW(LLThreadSafeQueueInterrupt());
 	} else if(status != APR_SUCCESS) {
-		throw LLThreadSafeQueueError("push failed");
+		LLTHROW(LLThreadSafeQueueError("push failed"));
 	} else {
 		; // Success.
 	}
@@ -88,9 +89,9 @@ void * LLThreadSafeQueueImplementation::popBack(void)
 	apr_status_t status = apr_queue_pop(mQueue, &element);
 
 	if(status == APR_EINTR) {
-		throw LLThreadSafeQueueInterrupt();
+		LLTHROW(LLThreadSafeQueueInterrupt());
 	} else if(status != APR_SUCCESS) {
-		throw LLThreadSafeQueueError("pop failed");
+		LLTHROW(LLThreadSafeQueueError("pop failed"));
 	} else {
 		return element;
 	}
diff --git a/indra/llcommon/llthreadsafequeue.h b/indra/llcommon/llthreadsafequeue.h
index 58cac38769..45289ef0b4 100644
--- a/indra/llcommon/llthreadsafequeue.h
+++ b/indra/llcommon/llthreadsafequeue.h
@@ -27,9 +27,8 @@
 #ifndef LL_LLTHREADSAFEQUEUE_H
 #define LL_LLTHREADSAFEQUEUE_H
 
-
+#include "llexception.h"
 #include <string>
-#include <stdexcept>
 
 
 struct apr_pool_t; // From apr_pools.h
@@ -40,11 +39,11 @@ class LLThreadSafeQueueImplementation; // See below.
 // A general queue exception.
 //
 class LL_COMMON_API LLThreadSafeQueueError:
-public std::runtime_error
+	public LLException
 {
 public:
 	LLThreadSafeQueueError(std::string const & message):
-	std::runtime_error(message)
+		LLException(message)
 	{
 		; // No op.
 	}
diff --git a/indra/llcommon/lltracerecording.cpp b/indra/llcommon/lltracerecording.cpp
index 0b10438b9f..3094b627a2 100644
--- a/indra/llcommon/lltracerecording.cpp
+++ b/indra/llcommon/lltracerecording.cpp
@@ -257,7 +257,13 @@ F64Kilobytes Recording::getMean(const StatType<MemAccumulator>& stat)
 	
 	if (active_accumulator && active_accumulator->mSize.hasValue())
 	{
-		return F64Bytes(lerp(accumulator.mSize.getMean(), active_accumulator->mSize.getMean(), active_accumulator->mSize.getSampleCount() / (accumulator.mSize.getSampleCount() + active_accumulator->mSize.getSampleCount())));
+        F32 t = 0.0f;
+        S32 div = accumulator.mSize.getSampleCount() + active_accumulator->mSize.getSampleCount();
+        if (div > 0)
+        {
+            t = active_accumulator->mSize.getSampleCount() / div;
+        }
+		return F64Bytes(lerp(accumulator.mSize.getMean(), active_accumulator->mSize.getMean(), t));
 	}
 	else
 	{
@@ -426,7 +432,13 @@ F64 Recording::getMean( const StatType<SampleAccumulator>& stat )
 	const SampleAccumulator* active_accumulator = mActiveBuffers ? &mActiveBuffers->mSamples[stat.getIndex()] : NULL;
 	if (active_accumulator && active_accumulator->hasValue())
 	{
-		return lerp(accumulator.getMean(), active_accumulator->getMean(), active_accumulator->getSampleCount() / (accumulator.getSampleCount() + active_accumulator->getSampleCount()));
+        F32 t = 0.0f;
+        S32 div = accumulator.getSampleCount() + active_accumulator->getSampleCount();
+        if (div > 0)
+        {
+            t = active_accumulator->getSampleCount() / div;
+        }
+		return lerp(accumulator.getMean(), active_accumulator->getMean(), t);
 	}
 	else
 	{
@@ -506,7 +518,13 @@ F64 Recording::getMean( const StatType<EventAccumulator>& stat )
 	const EventAccumulator* active_accumulator = mActiveBuffers ? &mActiveBuffers->mEvents[stat.getIndex()] : NULL;
 	if (active_accumulator && active_accumulator->hasValue())
 	{
-		return lerp(accumulator.getMean(), active_accumulator->getMean(), active_accumulator->getSampleCount() / (accumulator.getSampleCount() + active_accumulator->getSampleCount()));
+		F32 t = 0.0f;
+        S32 div = accumulator.getSampleCount() + active_accumulator->getSampleCount();
+        if (div > 0)
+        {
+            t = active_accumulator->getSampleCount() / div;
+        }
+		return lerp(accumulator.getMean(), active_accumulator->getMean(), t);
 	}
 	else
 	{
diff --git a/indra/llcommon/lluriparser.cpp b/indra/llcommon/lluriparser.cpp
index 82d0dc8b4b..c275b90120 100644
--- a/indra/llcommon/lluriparser.cpp
+++ b/indra/llcommon/lluriparser.cpp
@@ -205,9 +205,9 @@ void LLUriParser::glue(std::string& uri) const
 	uri = first_part + second_part;
 }
 
-void LLUriParser::glueFirst(std::string& uri) const
+void LLUriParser::glueFirst(std::string& uri, bool use_scheme) const
 {
-	if (mScheme.size())
+	if (use_scheme && mScheme.size())
 	{
 		uri = mScheme;
 		uri += "://";
diff --git a/indra/llcommon/lluriparser.h b/indra/llcommon/lluriparser.h
index 2df8085ae6..cfbf54f3c8 100644
--- a/indra/llcommon/lluriparser.h
+++ b/indra/llcommon/lluriparser.h
@@ -60,7 +60,7 @@ public:
 
 	void extractParts();
 	void glue(std::string& uri) const;
-	void glueFirst(std::string& uri) const;
+	void glueFirst(std::string& uri, bool use_scheme = true) const;
 	void glueSecond(std::string& uri) const;
 	bool test() const;
 	S32 normalize();
diff --git a/indra/llcommon/lluuid.cpp b/indra/llcommon/lluuid.cpp
index e3671047b4..d4af2c6b01 100644
--- a/indra/llcommon/lluuid.cpp
+++ b/indra/llcommon/lluuid.cpp
@@ -83,7 +83,7 @@ unsigned int decode( char const * fiveChars ) throw( bad_input_data )
 unsigned int ret = 0;
 for( int ix = 0; ix < 5; ++ix ) {
 char * s = strchr( encodeTable, fiveChars[ ix ] );
-if( s == 0 ) throw bad_input_data();
+if( s == 0 ) LLTHROW(bad_input_data());
 ret = ret * 85 + (s-encodeTable);
 }
 return ret;
diff --git a/indra/llcommon/tests/llerror_test.cpp b/indra/llcommon/tests/llerror_test.cpp
index f51279e817..20de205454 100644
--- a/indra/llcommon/tests/llerror_test.cpp
+++ b/indra/llcommon/tests/llerror_test.cpp
@@ -237,8 +237,21 @@ namespace tut
 	void ErrorTestObject::test<4>()
 		// file abbreviation
 	{
-		std::string thisFile = __FILE__;
-		std::string abbreviateFile = LLError::abbreviateFile(thisFile);
+		std::string prev, abbreviateFile = __FILE__;
+        do
+        {
+            prev = abbreviateFile;
+            abbreviateFile = LLError::abbreviateFile(abbreviateFile);
+            // __FILE__ is assumed to end with
+            // indra/llcommon/tests/llerror_test.cpp. This test used to call
+            // abbreviateFile() exactly once, then check below whether it
+            // still contained the string 'indra'. That fails if the FIRST
+            // part of the pathname also contains indra! Certain developer
+            // machine images put local directory trees under
+            // /ngi-persist/indra, which is where we observe the problem. So
+            // now, keep calling abbreviateFile() until it returns its
+            // argument unchanged, THEN check.
+        } while (abbreviateFile != prev);
 
 		ensure_ends_with("file name abbreviation",
 			abbreviateFile,
@@ -551,9 +564,9 @@ namespace tut
 					function;
 		writeReturningLocationAndFunction(location, function);
 
-		ensure_equals("order is location time type function message",
+		ensure_equals("order is time location type function message",
 			message(0),
-			location + roswell() + " INFO: " + function + ": apple");
+			roswell() + " INFO: " + location + function + ": apple");
 	}
 
 	template<> template<>
diff --git a/indra/llcommon/tests/llexception_test.cpp b/indra/llcommon/tests/llexception_test.cpp
new file mode 100644
index 0000000000..6bee1943c2
--- /dev/null
+++ b/indra/llcommon/tests/llexception_test.cpp
@@ -0,0 +1,308 @@
+/**
+ * @file   llexception_test.cpp
+ * @author Nat Goodspeed
+ * @date   2016-08-12
+ * @brief  Tests for throwing exceptions.
+ *
+ * This isn't a regression test: it doesn't need to be run every build, which
+ * is why the corresponding line in llcommon/CMakeLists.txt is commented out.
+ * Rather it's a head-to-head test of what kind of exception information we
+ * can collect from various combinations of exception base classes, type of
+ * throw verb and sequences of catch clauses.
+ *
+ * This "test" makes no ensure() calls: its output goes to stdout for human
+ * examination.
+ *
+ * As of 2016-08-12 with Boost 1.57, we come to the following conclusions.
+ * These should probably be re-examined from time to time as we update Boost.
+ *
+ * - It is indisputably beneficial to use BOOST_THROW_EXCEPTION() rather than
+ *   plain throw. The macro annotates the exception object with the filename,
+ *   line number and function name from which the exception was thrown.
+ *
+ * - That being the case, deriving only from boost::exception isn't an option.
+ *   Every exception object passed to BOOST_THROW_EXCEPTION() must be derived
+ *   directly or indirectly from std::exception. The only question is whether
+ *   to also derive from boost::exception. We decided to derive LLException
+ *   from both, as it makes message output slightly cleaner, but this is a
+ *   trivial reason: if a strong reason emerges to prefer single inheritance,
+ *   dropping the boost::exception base class shouldn't be a problem.
+ *
+ * - (As you will have guessed, ridiculous things like a char* or int or a
+ *   class derived from neither boost::exception nor std::exception can only
+ *   be caught by that specific type or (...), and
+ *   boost::current_exception_diagnostic_information() simply throws up its
+ *   hands and confesses utter ignorance. Stay away from such nonsense.)
+ *
+ * - But if you derive from std::exception, to nat's surprise,
+ *   boost::current_exception_diagnostic_information() gives as much
+ *   information about exceptions in a catch (...) clause as you can get from
+ *   a specific catch (const std::exception&) clause, notably the concrete
+ *   exception class and the what() string. So instead of a sequence like
+ *
+ *   try { ... }
+ *   catch (const boost::exception& e) { ... boost-flavored logging ... }
+ *   catch (const std::exception& e)   { ... std::exception logging ... }
+ *   catch (...)                       { ... generic logging ... }
+ *
+ *   we should be able to get away with only a catch (...) clause that logs
+ *   boost::current_exception_diagnostic_information().
+ *
+ * - Going further: boost::current_exception_diagnostic_information() provides
+ *   just as much information even within a std::set_terminate() handler. So
+ *   it might not even be strictly necessary to include a catch (...) clause
+ *   since the viewer does use std::set_terminate().
+ *
+ * - (We might consider adding a catch (int) clause because Kakadu internally
+ *   throws ints, and who knows if one of those might leak out. If it does,
+ *   boost::current_exception_diagnostic_information() can do nothing with it.
+ *   A catch (int) clause could at least log the value and rethrow.)
+ *
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llexception.h"
+// STL headers
+// std headers
+#include <typeinfo>
+// external library headers
+#include <boost/throw_exception.hpp>
+// other Linden headers
+#include "../test/lltut.h"
+
+// helper for display output
+// usage: std::cout << center(some string value, fill char, width) << std::endl;
+// (assumes it's the only thing on that particular line)
+struct center
+{
+    center(const std::string& label, char fill, std::size_t width):
+        mLabel(label),
+        mFill(fill),
+        mWidth(width)
+    {}
+
+    // Use friend declaration not because we need to grant access, but because
+    // it lets us declare a free operator like a member function.
+    friend std::ostream& operator<<(std::ostream& out, const center& ctr)
+    {
+        std::size_t padded = ctr.mLabel.length() + 2;
+        std::size_t left  = (ctr.mWidth - padded) / 2;
+        std::size_t right = ctr.mWidth - left - padded;
+        return out << std::string(left, ctr.mFill) << ' ' << ctr.mLabel << ' '
+                   << std::string(right, ctr.mFill);
+    }
+
+    std::string mLabel;
+    char mFill;
+    std::size_t mWidth;
+};
+
+/*****************************************************************************
+*   Four kinds of exceptions: derived from boost::exception, from
+*   std::exception, from both, from neither
+*****************************************************************************/
+// Interestingly, we can't use this variant with BOOST_THROW_EXCEPTION()
+// (which we want) -- we reach a failure topped by this comment:
+//  //All boost exceptions are required to derive from std::exception,
+//  //to ensure compatibility with BOOST_NO_EXCEPTIONS.
+struct FromBoost: public boost::exception
+{
+    FromBoost(const std::string& what): mWhat(what) {}
+    ~FromBoost() throw() {}
+    std::string what() const { return mWhat; }
+    std::string mWhat;
+};
+
+struct FromStd: public std::runtime_error
+{
+    FromStd(const std::string& what): std::runtime_error(what) {}
+};
+
+struct FromBoth: public boost::exception, public std::runtime_error
+{
+    FromBoth(const std::string& what): std::runtime_error(what) {}
+};
+
+// Same deal with FromNeither: can't use with BOOST_THROW_EXCEPTION().
+struct FromNeither
+{
+    FromNeither(const std::string& what): mWhat(what) {}
+    std::string what() const { return mWhat; }
+    std::string mWhat;
+};
+
+/*****************************************************************************
+*   Two kinds of throws: plain throw and BOOST_THROW_EXCEPTION()
+*****************************************************************************/
+template <typename EXC>
+void plain_throw(const std::string& what)
+{
+    throw EXC(what);
+}
+
+template <typename EXC>
+void boost_throw(const std::string& what)
+{
+    BOOST_THROW_EXCEPTION(EXC(what));
+}
+
+// Okay, for completeness, functions that throw non-class values. We wouldn't
+// even deign to consider these if we hadn't found examples in our own source
+// code! (Note that Kakadu's internal exception support is still based on
+// throwing ints.)
+void throw_char_ptr(const std::string& what)
+{
+    throw what.c_str(); // umm...
+}
+
+void throw_int(const std::string& what)
+{
+    throw int(what.length());
+}
+
+/*****************************************************************************
+*   Three sequences of catch clauses:
+*   boost::exception then ...,
+*   std::exception then ...,
+*   or just ...
+*****************************************************************************/
+void catch_boost_dotdotdot(void (*thrower)(const std::string&), const std::string& what)
+{
+    try
+    {
+        thrower(what);
+    }
+    catch (const boost::exception& e)
+    {
+        std::cout << "catch (const boost::exception& e)" << std::endl;
+        std::cout << "e is " << typeid(e).name() << std::endl;
+        std::cout << "boost::diagnostic_information(e):\n'"
+                  << boost::diagnostic_information(e) << "'" << std::endl;
+        // no way to report e.what()
+    }
+    catch (...)
+    {
+        std::cout << "catch (...)" << std::endl;
+        std::cout << "boost::current_exception_diagnostic_information():\n'"
+                  << boost::current_exception_diagnostic_information() << "'"
+                  << std::endl;
+    }
+}
+
+void catch_std_dotdotdot(void (*thrower)(const std::string&), const std::string& what)
+{
+    try
+    {
+        thrower(what);
+    }
+    catch (const std::exception& e)
+    {
+        std::cout << "catch (const std::exception& e)" << std::endl;
+        std::cout << "e is " << typeid(e).name() << std::endl;
+        std::cout << "boost::diagnostic_information(e):\n'"
+                  << boost::diagnostic_information(e) << "'" << std::endl;
+        std::cout << "e.what: '"
+                  << e.what() << "'" << std::endl;
+    }
+    catch (...)
+    {
+        std::cout << "catch (...)" << std::endl;
+        std::cout << "boost::current_exception_diagnostic_information():\n'"
+                  << boost::current_exception_diagnostic_information() << "'"
+                  << std::endl;
+    }
+}
+
+void catch_dotdotdot(void (*thrower)(const std::string&), const std::string& what)
+{
+    try
+    {
+        thrower(what);
+    }
+    catch (...)
+    {
+        std::cout << "catch (...)" << std::endl;
+        std::cout << "boost::current_exception_diagnostic_information():\n'"
+                  << boost::current_exception_diagnostic_information() << "'"
+                  << std::endl;
+    }
+}
+
+/*****************************************************************************
+*   Try a particular kind of throw against each of three catch sequences
+*****************************************************************************/
+void catch_several(void (*thrower)(const std::string&), const std::string& what)
+{
+    std::cout << std::string(20, '-') << "catch_boost_dotdotdot(" << what << ")" << std::endl;
+    catch_boost_dotdotdot(thrower, "catch_boost_dotdotdot(" + what + ")");
+
+    std::cout << std::string(20, '-') << "catch_std_dotdotdot(" << what << ")" << std::endl;
+    catch_std_dotdotdot(thrower, "catch_std_dotdotdot(" + what + ")");
+
+    std::cout << std::string(20, '-') << "catch_dotdotdot(" << what << ")" << std::endl;
+    catch_dotdotdot(thrower, "catch_dotdotdot(" + what + ")");
+}
+
+/*****************************************************************************
+*   For a particular kind of exception, try both kinds of throw against all
+*   three catch sequences
+*****************************************************************************/
+template <typename EXC>
+void catch_both_several(const std::string& what)
+{
+    std::cout << std::string(20, '*') << "plain_throw<" << what << ">" << std::endl;
+    catch_several(plain_throw<EXC>, "plain_throw<" + what + ">");
+
+    std::cout << std::string(20, '*') << "boost_throw<" << what << ">" << std::endl;
+    catch_several(boost_throw<EXC>, "boost_throw<" + what + ">");
+}
+
+/*****************************************************************************
+*   TUT
+*****************************************************************************/
+namespace tut
+{
+    struct llexception_data
+    {
+    };
+    typedef test_group<llexception_data> llexception_group;
+    typedef llexception_group::object object;
+    llexception_group llexceptiongrp("llexception");
+
+    template<> template<>
+    void object::test<1>()
+    {
+        set_test_name("throwing exceptions");
+
+        // For each kind of exception, try both kinds of throw against all
+        // three catch sequences
+        std::size_t margin = 72;
+        std::cout << center("FromStd", '=', margin) << std::endl;
+        catch_both_several<FromStd>("FromStd");
+
+        std::cout << center("FromBoth", '=', margin) << std::endl;
+        catch_both_several<FromBoth>("FromBoth");
+
+        std::cout << center("FromBoost", '=', margin) << std::endl;
+        // can't throw with BOOST_THROW_EXCEPTION(), just use catch_several()
+        catch_several(plain_throw<FromBoost>, "plain_throw<FromBoost>");
+
+        std::cout << center("FromNeither", '=', margin) << std::endl;
+        // can't throw this with BOOST_THROW_EXCEPTION() either
+        catch_several(plain_throw<FromNeither>, "plain_throw<FromNeither>");
+
+        std::cout << center("const char*", '=', margin) << std::endl;
+        // We don't expect BOOST_THROW_EXCEPTION() to throw anything so daft
+        // as a const char* or an int, so don't bother with
+        // catch_both_several() -- just catch_several().
+        catch_several(throw_char_ptr, "throw_char_ptr");
+
+        std::cout << center("int", '=', margin) << std::endl;
+        catch_several(throw_int, "throw_int");
+    }
+} // namespace tut
diff --git a/indra/llcommon/tests/llheteromap_test.cpp b/indra/llcommon/tests/llheteromap_test.cpp
new file mode 100644
index 0000000000..686bffb878
--- /dev/null
+++ b/indra/llcommon/tests/llheteromap_test.cpp
@@ -0,0 +1,163 @@
+/**
+ * @file   llheteromap_test.cpp
+ * @author Nat Goodspeed
+ * @date   2016-10-12
+ * @brief  Test for llheteromap.
+ * 
+ * $LicenseInfo:firstyear=2016&license=viewerlgpl$
+ * Copyright (c) 2016, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llheteromap.h"
+// STL headers
+#include <set>
+// std headers
+// external library headers
+
+// (pacify clang)
+std::ostream& operator<<(std::ostream& out, const std::set<std::string>& strset);
+// other Linden headers
+#include "../test/lltut.h"
+
+static std::string clog;
+static std::set<std::string> dlog;
+
+// want to be able to use ensure_equals() on a set<string>
+std::ostream& operator<<(std::ostream& out, const std::set<std::string>& strset)
+{
+    out << '{';
+    const char* delim = "";
+    for (std::set<std::string>::const_iterator si(strset.begin()), se(strset.end());
+         si != se; ++si)
+    {
+        out << delim << '"' << *si << '"';
+        delim = ", ";
+    }
+    out << '}';
+    return out;
+}
+
+// unrelated test classes
+struct Chalk
+{
+    int dummy;
+    std::string name;
+
+    Chalk():
+        dummy(0)
+    {
+        clog.append("a");
+    }
+
+    ~Chalk()
+    {
+        dlog.insert("a");
+    }
+
+private:
+    Chalk(const Chalk&);            // no implementation
+};
+
+struct Cheese
+{
+    std::string name;
+
+    Cheese()
+    {
+        clog.append("e");
+    }
+
+    ~Cheese()
+    {
+        dlog.insert("e");
+    }
+
+private:
+    Cheese(const Cheese&);          // no implementation
+};
+
+struct Chowdah
+{
+    char displace[17];
+    std::string name;
+
+    Chowdah()
+    {
+        displace[0] = '\0';
+        clog.append("o");
+    }
+
+    ~Chowdah()
+    {
+        dlog.insert("o");
+    }
+
+private:
+    Chowdah(const Chowdah&);        // no implementation
+};
+
+/*****************************************************************************
+*   TUT
+*****************************************************************************/
+namespace tut
+{
+    struct llheteromap_data
+    {
+        llheteromap_data()
+        {
+            clog.erase();
+            dlog.clear();
+        }
+    };
+    typedef test_group<llheteromap_data> llheteromap_group;
+    typedef llheteromap_group::object object;
+    llheteromap_group llheteromapgrp("llheteromap");
+
+    template<> template<>
+    void object::test<1>()
+    {
+        set_test_name("create, get, delete");
+
+        {
+            LLHeteroMap map;
+
+            {
+                // create each instance
+                Chalk& chalk = map.obtain<Chalk>();
+                chalk.name = "Chalk";
+
+                Cheese& cheese = map.obtain<Cheese>();
+                cheese.name = "Cheese";
+
+                Chowdah& chowdah = map.obtain<Chowdah>();
+                chowdah.name = "Chowdah";
+            } // refs go out of scope
+
+            {
+                // verify each instance
+                Chalk& chalk = map.obtain<Chalk>();
+                ensure_equals(chalk.name, "Chalk");
+
+                Cheese& cheese = map.obtain<Cheese>();
+                ensure_equals(cheese.name, "Cheese");
+
+                Chowdah& chowdah = map.obtain<Chowdah>();
+                ensure_equals(chowdah.name, "Chowdah");
+            }
+        } // destroy map
+
+        // Chalk, Cheese and Chowdah should have been created in specific order
+        ensure_equals(clog, "aeo");
+
+        // We don't care what order they're destroyed in, as long as each is
+        // appropriately destroyed.
+        std::set<std::string> dtorset;
+        for (const char* cp = "aeo"; *cp; ++cp)
+            dtorset.insert(std::string(1, *cp));
+        ensure_equals(dlog, dtorset);
+    }
+} // namespace tut
diff --git a/indra/llcommon/tests/llleap_test.cpp b/indra/llcommon/tests/llleap_test.cpp
index d342dece84..c387da6c48 100644
--- a/indra/llcommon/tests/llleap_test.cpp
+++ b/indra/llcommon/tests/llleap_test.cpp
@@ -110,10 +110,7 @@ namespace tut
                    // finding indra/lib/python. Use our __FILE__, with
                    // raw-string syntax to deal with Windows pathnames.
                    "mydir = os.path.dirname(r'" << __FILE__ << "')\n"
-                   // We expect mydir to be .../indra/llcommon/tests.
-                   "sys.path.insert(0,\n"
-                   "    os.path.join(mydir, os.pardir, os.pardir, 'lib', 'python'))\n"
-                   "from indra.base import llsd\n"
+                   "from llbase import llsd\n"
                    "\n"
                    "class ProtocolError(Exception):\n"
                    "    def __init__(self, msg, data):\n"
diff --git a/indra/llcommon/tests/llpounceable_test.cpp b/indra/llcommon/tests/llpounceable_test.cpp
new file mode 100644
index 0000000000..2f4915ce11
--- /dev/null
+++ b/indra/llcommon/tests/llpounceable_test.cpp
@@ -0,0 +1,230 @@
+/**
+ * @file   llpounceable_test.cpp
+ * @author Nat Goodspeed
+ * @date   2015-05-22
+ * @brief  Test for llpounceable.
+ * 
+ * $LicenseInfo:firstyear=2015&license=viewerlgpl$
+ * Copyright (c) 2015, Linden Research, Inc.
+ * $/LicenseInfo$
+ */
+
+// Precompiled header
+#include "linden_common.h"
+// associated header
+#include "llpounceable.h"
+// STL headers
+// std headers
+// external library headers
+#include <boost/bind.hpp>
+// other Linden headers
+#include "../test/lltut.h"
+
+/*----------------------------- string testing -----------------------------*/
+void append(std::string* dest, const std::string& src)
+{
+    dest->append(src);
+}
+
+/*-------------------------- Data-struct testing ---------------------------*/
+struct Data
+{
+    Data(const std::string& data):
+        mData(data)
+    {}
+    const std::string mData;
+};
+
+void setter(Data** dest, Data* ptr)
+{
+    *dest = ptr;
+}
+
+static Data* static_check = 0;
+
+// Set up an extern pointer to an LLPounceableStatic so the linker will fill
+// in the forward reference from below, before runtime.
+extern LLPounceable<Data*, LLPounceableStatic> gForward;
+
+struct EnqueueCall
+{
+    EnqueueCall()
+    {
+        // Intentionally use a forward reference to an LLPounceableStatic that
+        // we believe is NOT YET CONSTRUCTED. This models the scenario in
+        // which a constructor in another translation unit runs before
+        // constructors in this one. We very specifically want callWhenReady()
+        // to work even in that case: we need the LLPounceableQueueImpl to be
+        // initialized even if the LLPounceable itself is not.
+        gForward.callWhenReady(boost::bind(setter, &static_check, _1));
+    }
+} nqcall;
+// When this declaration is processed, we should enqueue the
+// setter(&static_check, _1) call for when gForward is set non-NULL. Needless
+// to remark, we want this call not to crash.
+
+// Now declare gForward. Its constructor should not run until after nqcall's.
+LLPounceable<Data*, LLPounceableStatic> gForward;
+
+/*****************************************************************************
+*   TUT
+*****************************************************************************/
+namespace tut
+{
+    struct llpounceable_data
+    {
+    };
+    typedef test_group<llpounceable_data> llpounceable_group;
+    typedef llpounceable_group::object object;
+    llpounceable_group llpounceablegrp("llpounceable");
+
+    template<> template<>
+    void object::test<1>()
+    {
+        set_test_name("LLPounceableStatic out-of-order test");
+        // LLPounceable<T, LLPounceableStatic>::callWhenReady() must work even
+        // before LLPounceable's constructor runs. That's the whole point of
+        // implementing it with an LLSingleton queue. This models (say)
+        // LLPounceableStatic<LLMessageSystem*, LLPounceableStatic>.
+        ensure("static_check should still be null", ! static_check);
+        Data myData("test<1>");
+        gForward = &myData;         // should run setter
+        ensure_equals("static_check should be &myData", static_check, &myData);
+    }
+
+    template<> template<>
+    void object::test<2>()
+    {
+        set_test_name("LLPounceableQueue different queues");
+        // We expect that LLPounceable<T, LLPounceableQueue> should have
+        // different queues because that specialization stores the queue
+        // directly in the LLPounceable instance.
+        Data *aptr = 0, *bptr = 0;
+        LLPounceable<Data*> a, b;
+        a.callWhenReady(boost::bind(setter, &aptr, _1));
+        b.callWhenReady(boost::bind(setter, &bptr, _1));
+        ensure("aptr should be null", ! aptr);
+        ensure("bptr should be null", ! bptr);
+        Data adata("a"), bdata("b");
+        a = &adata;
+        ensure_equals("aptr should be &adata", aptr, &adata);
+        // but we haven't yet set b
+        ensure("bptr should still be null", !bptr);
+        b = &bdata;
+        ensure_equals("bptr should be &bdata", bptr, &bdata);
+    }
+
+    template<> template<>
+    void object::test<3>()
+    {
+        set_test_name("LLPounceableStatic different queues");
+        // LLPounceable<T, LLPounceableStatic> should also have a distinct
+        // queue for each instance, but that engages an additional map lookup
+        // because there's only one LLSingleton for each T.
+        Data *aptr = 0, *bptr = 0;
+        LLPounceable<Data*, LLPounceableStatic> a, b;
+        a.callWhenReady(boost::bind(setter, &aptr, _1));
+        b.callWhenReady(boost::bind(setter, &bptr, _1));
+        ensure("aptr should be null", ! aptr);
+        ensure("bptr should be null", ! bptr);
+        Data adata("a"), bdata("b");
+        a = &adata;
+        ensure_equals("aptr should be &adata", aptr, &adata);
+        // but we haven't yet set b
+        ensure("bptr should still be null", !bptr);
+        b = &bdata;
+        ensure_equals("bptr should be &bdata", bptr, &bdata);
+    }
+
+    template<> template<>
+    void object::test<4>()
+    {
+        set_test_name("LLPounceable<T> looks like T");
+        // We want LLPounceable<T, TAG> to be drop-in replaceable for a plain
+        // T for read constructs. In particular, it should behave like a dumb
+        // pointer -- and with zero abstraction cost for such usage.
+        Data* aptr = 0;
+        Data a("a");
+        // should be able to initialize a pounceable (when its constructor
+        // runs)
+        LLPounceable<Data*> pounceable(&a);
+        // should be able to pass LLPounceable<T> to function accepting T
+        setter(&aptr, pounceable);
+        ensure_equals("aptr should be &a", aptr, &a);
+        // should be able to dereference with *
+        ensure_equals("deref with *", (*pounceable).mData, "a");
+        // should be able to dereference with ->
+        ensure_equals("deref with ->", pounceable->mData, "a");
+        // bool operations
+        ensure("test with operator bool()", pounceable);
+        ensure("test with operator !()", ! (! pounceable));
+    }
+
+    template<> template<>
+    void object::test<5>()
+    {
+        set_test_name("Multiple callWhenReady() queue items");
+        Data *p1 = 0, *p2 = 0, *p3 = 0;
+        Data a("a");
+        LLPounceable<Data*> pounceable;
+        // queue up a couple setter() calls for later
+        pounceable.callWhenReady(boost::bind(setter, &p1, _1));
+        pounceable.callWhenReady(boost::bind(setter, &p2, _1));
+        // should still be pending
+        ensure("p1 should be null", !p1);
+        ensure("p2 should be null", !p2);
+        ensure("p3 should be null", !p3);
+        pounceable = 0;
+        // assigning a new empty value shouldn't flush the queue
+        ensure("p1 should still be null", !p1);
+        ensure("p2 should still be null", !p2);
+        ensure("p3 should still be null", !p3);
+        // using whichever syntax
+        pounceable.reset(0);
+        // try to make ensure messages distinct... tough to pin down which
+        // ensure() failed if multiple ensure() calls in the same test<n> have
+        // the same message!
+        ensure("p1 should again be null", !p1);
+        ensure("p2 should again be null", !p2);
+        ensure("p3 should again be null", !p3);
+        pounceable.reset(&a);       // should flush queue
+        ensure_equals("p1 should be &a", p1, &a);
+        ensure_equals("p2 should be &a", p2, &a);
+        ensure("p3 still not set", !p3);
+        // immediate call
+        pounceable.callWhenReady(boost::bind(setter, &p3, _1));
+        ensure_equals("p3 should be &a", p3, &a);
+    }
+
+    template<> template<>
+    void object::test<6>()
+    {
+        set_test_name("queue order");
+        std::string data;
+        LLPounceable<std::string*> pounceable;
+        pounceable.callWhenReady(boost::bind(append, _1, "a"));
+        pounceable.callWhenReady(boost::bind(append, _1, "b"));
+        pounceable.callWhenReady(boost::bind(append, _1, "c"));
+        pounceable = &data;
+        ensure_equals("callWhenReady() must preserve chronological order",
+                      data, "abc");
+
+        std::string data2;
+        pounceable = NULL;
+        pounceable.callWhenReady(boost::bind(append, _1, "d"));
+        pounceable.callWhenReady(boost::bind(append, _1, "e"));
+        pounceable.callWhenReady(boost::bind(append, _1, "f"));
+        pounceable = &data2;
+        ensure_equals("LLPounceable must reset queue when fired",
+                      data2, "def");
+    }
+
+    template<> template<>
+    void object::test<7>()
+    {
+        set_test_name("compile-fail test, uncomment to check");
+        // The following declaration should fail: only LLPounceableQueue and
+        // LLPounceableStatic should work as tags.
+//      LLPounceable<Data*, int> pounceable;
+    }
+} // namespace tut
diff --git a/indra/llcommon/tests/llsdserialize_test.cpp b/indra/llcommon/tests/llsdserialize_test.cpp
index 6fbb9abfc0..81b930e1e2 100644
--- a/indra/llcommon/tests/llsdserialize_test.cpp
+++ b/indra/llcommon/tests/llsdserialize_test.cpp
@@ -1518,10 +1518,7 @@ namespace tut
             // scanner.
             import_llsd("import os.path\n"
                         "import sys\n"
-                        "sys.path.insert(0,\n"
-                        "    os.path.join(os.path.dirname(r'" __FILE__ "'),\n"
-                        "                 os.pardir, os.pardir, 'lib', 'python'))\n"
-                        "from indra.base import llsd\n")
+                        "from llbase import llsd\n")
         {}
         ~TestPythonCompatible() {}
 
diff --git a/indra/llcommon/tests/llsingleton_test.cpp b/indra/llcommon/tests/llsingleton_test.cpp
index 385289aefe..56886bc73f 100644
--- a/indra/llcommon/tests/llsingleton_test.cpp
+++ b/indra/llcommon/tests/llsingleton_test.cpp
@@ -30,47 +30,172 @@
 #include "llsingleton.h"
 #include "../test/lltut.h"
 
+
+// Capture execution sequence by appending to log string.
+std::string sLog;
+
+#define DECLARE_CLASS(CLS)                          \
+struct CLS: public LLSingleton<CLS>                 \
+{                                                   \
+    LLSINGLETON(CLS);                               \
+    ~CLS();                                         \
+public:                                             \
+    static enum dep_flag {                          \
+        DEP_NONE, /* no dependency */               \
+        DEP_CTOR, /* dependency in ctor */          \
+        DEP_INIT  /* dependency in initSingleton */ \
+    } sDepFlag;                                     \
+                                                    \
+    void initSingleton();                           \
+    void cleanupSingleton();                        \
+};                                                  \
+                                                    \
+CLS::dep_flag CLS::sDepFlag = DEP_NONE
+
+DECLARE_CLASS(A);
+DECLARE_CLASS(B);
+
+#define DEFINE_MEMBERS(CLS, OTHER)              \
+CLS::CLS()                                      \
+{                                               \
+    sLog.append(#CLS);                          \
+    if (sDepFlag == DEP_CTOR)                   \
+    {                                           \
+        (void)OTHER::instance();                \
+    }                                           \
+}                                               \
+                                                \
+void CLS::initSingleton()                       \
+{                                               \
+    sLog.append("i" #CLS);                      \
+    if (sDepFlag == DEP_INIT)                   \
+    {                                           \
+        (void)OTHER::instance();                \
+    }                                           \
+}                                               \
+                                                \
+void CLS::cleanupSingleton()                    \
+{                                               \
+    sLog.append("x" #CLS);                      \
+}                                               \
+                                                \
+CLS::~CLS()                                     \
+{                                               \
+    sLog.append("~" #CLS);                      \
+}
+
+DEFINE_MEMBERS(A, B)
+DEFINE_MEMBERS(B, A)
+
 namespace tut
 {
-	struct singleton
-	{
-		// We need a class created with the LLSingleton template to test with.
-		class LLSingletonTest: public LLSingleton<LLSingletonTest>
-		{
-
-		};
-	};
-
-	typedef test_group<singleton> singleton_t;
-	typedef singleton_t::object singleton_object_t;
-	tut::singleton_t tut_singleton("LLSingleton");
-
-	template<> template<>
-	void singleton_object_t::test<1>()
-	{
-
-	}
-	template<> template<>
-	void singleton_object_t::test<2>()
-	{
-		LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
-		ensure(singleton_test);
-	}
-	template<> template<>
-	void singleton_object_t::test<3>()
-	{
-		//Construct the instance
-		LLSingletonTest::getInstance();
-		ensure(LLSingletonTest::instanceExists());
-
-		//Delete the instance
-		LLSingletonTest::deleteSingleton();
-		ensure(LLSingletonTest::destroyed());
-		ensure(!LLSingletonTest::instanceExists());
-
-		//Construct it again.
-		LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
-		ensure(singleton_test);
-		ensure(LLSingletonTest::instanceExists());
-	}
+    struct singleton
+    {
+        // We need a class created with the LLSingleton template to test with.
+        class LLSingletonTest: public LLSingleton<LLSingletonTest>
+        {
+            LLSINGLETON_EMPTY_CTOR(LLSingletonTest);
+        };
+    };
+
+    typedef test_group<singleton> singleton_t;
+    typedef singleton_t::object singleton_object_t;
+    tut::singleton_t tut_singleton("LLSingleton");
+
+    template<> template<>
+    void singleton_object_t::test<1>()
+    {
+
+    }
+    template<> template<>
+    void singleton_object_t::test<2>()
+    {
+        LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
+        ensure(singleton_test);
+    }
+
+    template<> template<>
+    void singleton_object_t::test<3>()
+    {
+        //Construct the instance
+        LLSingletonTest::getInstance();
+        ensure(LLSingletonTest::instanceExists());
+
+        //Delete the instance
+        LLSingletonTest::deleteSingleton();
+        ensure(!LLSingletonTest::instanceExists());
+
+        //Construct it again.
+        LLSingletonTest* singleton_test = LLSingletonTest::getInstance();
+        ensure(singleton_test);
+        ensure(LLSingletonTest::instanceExists());
+    }
+
+#define TESTS(CLS, OTHER, N0, N1, N2, N3)                               \
+    template<> template<>                                               \
+    void singleton_object_t::test<N0>()                                 \
+    {                                                                   \
+        set_test_name("just " #CLS);                                    \
+        CLS::sDepFlag = CLS::DEP_NONE;                                  \
+        OTHER::sDepFlag = OTHER::DEP_NONE;                              \
+        sLog.clear();                                                   \
+                                                                        \
+        (void)CLS::instance();                                          \
+        ensure_equals(sLog, #CLS "i" #CLS);                             \
+        LLSingletonBase::cleanupAll();                                  \
+        ensure_equals(sLog, #CLS "i" #CLS "x" #CLS);                    \
+        LLSingletonBase::deleteAll();                                   \
+        ensure_equals(sLog, #CLS "i" #CLS "x" #CLS "~" #CLS);           \
+    }                                                                   \
+                                                                        \
+    template<> template<>                                               \
+    void singleton_object_t::test<N1>()                                 \
+    {                                                                   \
+        set_test_name(#CLS " ctor depends " #OTHER);                    \
+        CLS::sDepFlag = CLS::DEP_CTOR;                                  \
+        OTHER::sDepFlag = OTHER::DEP_NONE;                              \
+        sLog.clear();                                                   \
+                                                                        \
+        (void)CLS::instance();                                          \
+        ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS);           \
+        LLSingletonBase::cleanupAll();                                  \
+        ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS "x" #CLS "x" #OTHER); \
+        LLSingletonBase::deleteAll();                                   \
+        ensure_equals(sLog, #CLS #OTHER "i" #OTHER "i" #CLS "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+    }                                                                   \
+                                                                        \
+    template<> template<>                                               \
+    void singleton_object_t::test<N2>()                                 \
+    {                                                                   \
+        set_test_name(#CLS " init depends " #OTHER);                    \
+        CLS::sDepFlag = CLS::DEP_INIT;                                  \
+        OTHER::sDepFlag = OTHER::DEP_NONE;                              \
+        sLog.clear();                                                   \
+                                                                        \
+        (void)CLS::instance();                                          \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER);           \
+        LLSingletonBase::cleanupAll();                                  \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER); \
+        LLSingletonBase::deleteAll();                                   \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+    }                                                                   \
+                                                                        \
+    template<> template<>                                               \
+    void singleton_object_t::test<N3>()                                 \
+    {                                                                   \
+        set_test_name(#CLS " circular init");                           \
+        CLS::sDepFlag = CLS::DEP_INIT;                                  \
+        OTHER::sDepFlag = OTHER::DEP_CTOR;                              \
+        sLog.clear();                                                   \
+                                                                        \
+        (void)CLS::instance();                                          \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER);           \
+        LLSingletonBase::cleanupAll();                                  \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER); \
+        LLSingletonBase::deleteAll();                                   \
+        ensure_equals(sLog, #CLS "i" #CLS #OTHER "i" #OTHER "x" #CLS "x" #OTHER "~" #CLS "~" #OTHER); \
+    }
+
+    TESTS(A, B, 4, 5, 6, 7)
+    TESTS(B, A, 8, 9, 10, 11)
 }
diff --git a/indra/llcommon/tests/wrapllerrs.h b/indra/llcommon/tests/wrapllerrs.h
index 785197ba11..9a4bbbd630 100644
--- a/indra/llcommon/tests/wrapllerrs.h
+++ b/indra/llcommon/tests/wrapllerrs.h
@@ -35,13 +35,13 @@
 
 #include <tut/tut.hpp>
 #include "llerrorcontrol.h"
+#include "llexception.h"
 #include "stringize.h"
 #include <boost/bind.hpp>
 #include <boost/noncopyable.hpp>
 #include <boost/shared_ptr.hpp>
 #include <list>
 #include <string>
-#include <stdexcept>
 
 // statically reference the function in test.cpp... it's short, we could
 // replicate, but better to reuse
@@ -67,9 +67,9 @@ struct WrapLLErrs
         LLError::restoreSettings(mPriorErrorSettings);
     }
 
-    struct FatalException: public std::runtime_error
+    struct FatalException: public LLException
     {
-        FatalException(const std::string& what): std::runtime_error(what) {}
+        FatalException(const std::string& what): LLException(what) {}
     };
 
     void operator()(const std::string& message)
@@ -78,7 +78,7 @@ struct WrapLLErrs
         error = message;
         // Also throw an appropriate exception since calling code is likely to
         // assume that control won't continue beyond LL_ERRS.
-        throw FatalException(message);
+        LLTHROW(FatalException(message));
     }
 
     std::string error;