DRTVWR-418: Remove final shutdown cleanup as a cause of crashes.

The recent LLSingleton work added a hook that would run during the C++
runtime's final destruction of static objects. When the LAST LLSingleton in
any module was destroyed, its destructor would call
LLSingletonBase::deleteAll(). That mechanism was intended to permit an
application consuming LLSingletons to skip making an explicit deleteAll()
call, knowing that all instantiated LLSingleton instances would eventually be
cleaned up anyway.

However -- experience proves that kicking off deleteAll() processing during
the C++ runtime's final cleanup is too late. Too much has already been
destroyed. That call tends to cause more shutdown crashes than it resolves.

This commit deletes that whole mechanism. Going forward, if you want to clean
up LLSingleton instances, you must explicitly call
LLSingletonBase::deleteAll() during the application lifetime. If you don't,
LLSingleton instances will simply be leaked -- which might be okay,
considering the application is terminating anyway.

1 files changed, 2 insertions, 44 deletions

diff --git a/indra/llcommon/llsingleton.cpp b/indra/llcommon/llsingleton.cpp
index 9025e53bb2..18e1b96a5f 100644
--- a/indra/llcommon/llsingleton.cpp
+++ b/indra/llcommon/llsingleton.cpp
@@ -369,62 +369,20 @@ void LLSingletonBase::deleteAll()
     }
 }
 
-/*------------------------ 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();
+    return 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;
+    // std::cerr, this would be a good place to use it.
 
     // Check LLError::is_available() because some of LLError's infrastructure
     // is itself an LLSingleton. If that LLSingleton has not yet been