Index: libstdc++-v3/config/os/mingw32-w64/os_defines.h
===================================================================
--- libstdc++-v3/config/os/mingw32-w64/os_defines.h	(revision 213759)
+++ libstdc++-v3/config/os/mingw32-w64/os_defines.h	(working copy)
@@ -78,4 +78,9 @@
 #define _GLIBCXX_LLP64 1
 #endif
 
+// Enable use of GetModuleHandleEx (requires Windows XP/2003) in
+// __cxa_thread_atexit to prevent modules from being unloaded before
+// their dtors are called
+#define _GLIBCXX_THREAD_ATEXIT_WIN32 1
+
 #endif
Index: libstdc++-v3/config/os/newlib/os_defines.h
===================================================================
--- libstdc++-v3/config/os/newlib/os_defines.h	(revision 213759)
+++ libstdc++-v3/config/os/newlib/os_defines.h	(working copy)
@@ -47,6 +47,12 @@
 
 // See libstdc++/20806.
 #define _GLIBCXX_HAVE_DOS_BASED_FILESYSTEM 1
+
+// Enable use of GetModuleHandleEx (requires Windows XP/2003) in
+// __cxa_thread_atexit to prevent modules from being unloaded before
+// their dtors are called
+#define _GLIBCXX_THREAD_ATEXIT_WIN32 1
+
 #endif
 
 #endif
Index: libstdc++-v3/libsupc++/atexit_thread.cc
===================================================================
--- libstdc++-v3/libsupc++/atexit_thread.cc	(revision 213759)
+++ libstdc++-v3/libsupc++/atexit_thread.cc	(working copy)
@@ -25,6 +25,10 @@
 #include <cstdlib>
 #include <new>
 #include "bits/gthr.h"
+#ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
 
 #if HAVE___CXA_THREAD_ATEXIT_IMPL
 
@@ -47,6 +51,9 @@
     void (*destructor)(void *);
     void *object;
     elt *next;
+#ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
+    HMODULE dll;
+#endif
   };
 
   // Keep a per-thread list of cleanups in gthread_key storage.
@@ -62,6 +69,11 @@
       {
 	elt *old_e = e;
 	e->destructor (e->object);
+#ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
+	/* Decrement DLL count */
+	if (e->dll)
+	  FreeLibrary (e->dll);
+#endif
 	e = e->next;
 	delete (old_e);
       }
@@ -133,6 +145,14 @@
   new_elt->destructor = dtor;
   new_elt->object = obj;
   new_elt->next = first;
+#ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
+  /* Store the DLL address for a later call to FreeLibrary in new_elt and
+     increment DLL load count.  This blocks the unloading of the DLL
+     before the thread-local dtors have been called.  This does NOT help
+     if FreeLibrary/dlclose is called in excess. */
+  GetModuleHandleExW (GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
+		      (LPCWSTR) dtor, &new_elt->dll);
+#endif
 
   if (__gthread_active_p ())
     __gthread_setspecific (key, new_elt);