2 files changed, 53 insertions, 1 deletions

diff --git a/indra/llcommon/llcoros.cpp b/indra/llcommon/llcoros.cpp
index b16f166d28..ea2d102de9 100644
--- a/indra/llcommon/llcoros.cpp
+++ b/indra/llcommon/llcoros.cpp
@@ -228,6 +228,22 @@ std::string LLCoros::logname()
     return data.mName.empty()? data.getKey() : data.mName;
 }
 
+void LLCoros::saveException(const std::string& name, std::exception_ptr exc)
+{
+    mExceptionQueue.emplace(name, exc);
+}
+
+void LLCoros::rethrow()
+{
+    if (! mExceptionQueue.empty())
+    {
+        ExceptionData front = mExceptionQueue.front();
+        mExceptionQueue.pop();
+        LL_WARNS("LLCoros") << "Rethrowing exception from coroutine " << front.name << LL_ENDL;
+        std::rethrow_exception(front.exception);
+    }
+}
+
 void LLCoros::setStackSize(S32 stacksize)
 {
     LL_DEBUGS("LLCoros") << "Setting coroutine stack size to " << stacksize << LL_ENDL;
@@ -370,7 +386,16 @@ void LLCoros::toplevel(std::string name, callable_t callable)
         // viewer will carry on.
         LOG_UNHANDLED_EXCEPTION(STRINGIZE("coroutine " << name));
     }
-    // uncaught exception by default will cause std::terminate()
+#ifndef LL_WINDOWS
+    catch (...)
+    {
+        // Stash any OTHER kind of uncaught exception in the rethrow() queue
+        // to be rethrown by the main fiber.
+        LL_WARNS("LLCoros") << "Capturing uncaught exception in coroutine "
+                            << name << LL_ENDL;
+        LLCoros::instance().saveException(name, std::current_exception());
+    }
+#endif // ! LL_WINDOWS
 }
 
 //static
diff --git a/indra/llcommon/llcoros.h b/indra/llcommon/llcoros.h
index 913414fbc1..c3820ae987 100644
--- a/indra/llcommon/llcoros.h
+++ b/indra/llcommon/llcoros.h
@@ -171,6 +171,19 @@ public:
     static std::string getName();
 
     /**
+     * rethrow() is called by the thread's main fiber to propagate an
+     * exception from any coroutine into the main fiber, where it can engage
+     * the normal unhandled-exception machinery, up to and including crash
+     * reporting.
+     *
+     * LLCoros maintains a queue of otherwise-uncaught exceptions from
+     * terminated coroutines. Each call to rethrow() pops the first of those
+     * and rethrows it. When the queue is empty (normal case), rethrow() is a
+     * no-op.
+     */
+    void rethrow();
+
+    /**
      * This variation returns a name suitable for log messages: the explicit
      * name for an explicitly-launched coroutine, or "mainN" for the default
      * coroutine on a thread.
@@ -314,6 +327,20 @@ private:
     void toplevel(std::string name, callable_t callable);
     struct CoroData;
     static CoroData& get_CoroData(const std::string& caller);
+    void saveException(const std::string& name, std::exception_ptr exc);
+
+    struct ExceptionData
+    {
+        ExceptionData(const std::string& nm, std::exception_ptr exc):
+            name(nm),
+            exception(exc)
+        {}
+        // name of coroutine that originally threw this exception
+        std::string name;
+        // the thrown exception
+        std::exception_ptr exception;
+    };
+    std::queue<ExceptionData> mExceptionQueue;
 
     S32 mStackSize;