re PR libstdc++/38732 (Openoffice.org segfaults with runtime libs built from GCC trunk)

	PR libstdc++/38732
	* libsupc++/unwind-cxx.h (__cxxabiv1::__cxa_exception): Remove
	referenceCount field again.
	(__cxxabiv1::__cxa_refcounted_exception): New struct.
	(__cxxabiv1::__get_refcounted_exception_header_from_obj,
	__cxxabiv1::__get_refcounted_exception_header_from_ue): New static
	inline functions.
	* libsupc++/eh_alloc.cc (__cxxabiv1::__cxa_allocate_exception,
	__cxxabiv1::__cxa_free_exception): Use __cxa_refcounted_exception
	instead of __cxa_exception.
	* libsupc++/eh_throw.cc (__gxx_exception_cleanup,
	__cxxabiv1::__cxa_throw): Likewise.
	* libsupc++/eh_ptr.cc (std::rethrow_exception,
	std::__exception_ptr::exception_ptr::_M_addref,
	std::__exception_ptr::exception_ptr::_M_release,
	__gxx_dependent_exception_cleanup): Likewise.
	* testsuite/18_support/exception/38732.cc: New test.

From-SVN: r143170

4 files changed, 60 insertions, 37 deletions

diff --git a/libstdc++-v3/libsupc++/eh_alloc.cc b/libstdc++-v3/libsupc++/eh_alloc.cc
index 6bc46fc..495a25f 100644
--- a/libstdc++-v3/libsupc++/eh_alloc.cc
+++ b/libstdc++-v3/libsupc++/eh_alloc.cc
@@ -1,5 +1,5 @@
 // -*- C++ -*- Allocate exception objects.
-// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2008
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009
 // Free Software Foundation, Inc.
 //
 // This file is part of GCC.
@@ -103,7 +103,7 @@ __cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) throw()
 {
   void *ret;
 
-  thrown_size += sizeof (__cxa_exception);
+  thrown_size += sizeof (__cxa_refcounted_exception);
   ret = malloc (thrown_size);
 
   if (! ret)
@@ -137,9 +137,9 @@ __cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) throw()
   __cxa_eh_globals *globals = __cxa_get_globals ();
   globals->uncaughtExceptions += 1;
 
-  memset (ret, 0, sizeof (__cxa_exception));
+  memset (ret, 0, sizeof (__cxa_refcounted_exception));
 
-  return (void *)((char *)ret + sizeof (__cxa_exception));
+  return (void *)((char *)ret + sizeof (__cxa_refcounted_exception));
 }
 
 
@@ -158,7 +158,7 @@ __cxxabiv1::__cxa_free_exception(void *vptr) throw()
       emergency_used &= ~((bitmask_type)1 << which);
     }
   else
-    free (ptr - sizeof (__cxa_exception));
+    free (ptr - sizeof (__cxa_refcounted_exception));
 }
 
 
diff --git a/libstdc++-v3/libsupc++/eh_ptr.cc b/libstdc++-v3/libsupc++/eh_ptr.cc
index 901219a..414a6b9 100644
--- a/libstdc++-v3/libsupc++/eh_ptr.cc
+++ b/libstdc++-v3/libsupc++/eh_ptr.cc
@@ -1,5 +1,5 @@
 // -*- C++ -*- Implement the members of exception_ptr.
-// Copyright (C) 2008 Free Software Foundation, Inc.
+// Copyright (C) 2008, 2009 Free Software Foundation, Inc.
 //
 // This file is part of GCC.
 //
@@ -84,8 +84,8 @@ std::__exception_ptr::exception_ptr::_M_addref() throw()
 {
   if (_M_exception_object)
     {
-      __cxa_exception *eh =
-        __get_exception_header_from_obj (_M_exception_object);
+      __cxa_refcounted_exception *eh =
+	__get_refcounted_exception_header_from_obj (_M_exception_object);
       __sync_add_and_fetch (&eh->referenceCount, 1);
     }
 }
@@ -96,12 +96,12 @@ std::__exception_ptr::exception_ptr::_M_release() throw()
 {
   if (_M_exception_object)
     {
-      __cxa_exception *eh =
-        __get_exception_header_from_obj (_M_exception_object);
+      __cxa_refcounted_exception *eh =
+	__get_refcounted_exception_header_from_obj (_M_exception_object);
       if (__sync_sub_and_fetch (&eh->referenceCount, 1) == 0)
         {
-          if (eh->exceptionDestructor)
-            eh->exceptionDestructor (_M_exception_object);
+	  if (eh->exc.exceptionDestructor)
+	    eh->exc.exceptionDestructor (_M_exception_object);
 
           __cxa_free_exception (_M_exception_object);
           _M_exception_object = 0;
@@ -191,22 +191,22 @@ __gxx_dependent_exception_cleanup (_Unwind_Reason_Code code,
 {
   // This cleanup is set only for dependents.
   __cxa_dependent_exception *dep = __get_dependent_exception_from_ue (exc);
-  __cxa_exception *header =
-    __get_exception_header_from_obj (dep->primaryException);
+  __cxa_refcounted_exception *header =
+    __get_refcounted_exception_header_from_obj (dep->primaryException);
 
   // We only want to be called through _Unwind_DeleteException.
   // _Unwind_DeleteException in the HP-UX IA64 libunwind library
   // returns _URC_NO_REASON and not _URC_FOREIGN_EXCEPTION_CAUGHT
   // like the GCC _Unwind_DeleteException function does.
   if (code != _URC_FOREIGN_EXCEPTION_CAUGHT && code != _URC_NO_REASON)
-    __terminate (header->terminateHandler);
+    __terminate (header->exc.terminateHandler);
 
   __cxa_free_dependent_exception (dep);
 
   if (__sync_sub_and_fetch (&header->referenceCount, 1) == 0)
     {
-      if (header->exceptionDestructor)
-        header->exceptionDestructor (header + 1);
+      if (header->exc.exceptionDestructor)
+	header->exc.exceptionDestructor (header + 1);
 
       __cxa_free_exception (header + 1);
     }
@@ -217,7 +217,8 @@ void
 std::rethrow_exception(std::exception_ptr ep)
 {
   void *obj = ep._M_get();
-  __cxa_exception *eh = __get_exception_header_from_obj (obj);
+  __cxa_refcounted_exception *eh
+    = __get_refcounted_exception_header_from_obj (obj);
 
   __cxa_dependent_exception *dep = __cxa_allocate_dependent_exception ();
   dep->primaryException = obj;
diff --git a/libstdc++-v3/libsupc++/eh_throw.cc b/libstdc++-v3/libsupc++/eh_throw.cc
index 24b3577..afe7c68 100644
--- a/libstdc++-v3/libsupc++/eh_throw.cc
+++ b/libstdc++-v3/libsupc++/eh_throw.cc
@@ -1,5 +1,5 @@
 // -*- C++ -*- Exception handling routines for throwing.
-// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 // Free Software Foundation, Inc.
 //
 // This file is part of GCC.
@@ -38,21 +38,22 @@ static void
 __gxx_exception_cleanup (_Unwind_Reason_Code code, _Unwind_Exception *exc)
 {
   // This cleanup is set only for primaries.
-  __cxa_exception *header = __get_exception_header_from_ue (exc);
+  __cxa_refcounted_exception *header
+    = __get_refcounted_exception_header_from_ue (exc);
 
   // We only want to be called through _Unwind_DeleteException.
   // _Unwind_DeleteException in the HP-UX IA64 libunwind library
   // returns _URC_NO_REASON and not _URC_FOREIGN_EXCEPTION_CAUGHT
   // like the GCC _Unwind_DeleteException function does.
   if (code != _URC_FOREIGN_EXCEPTION_CAUGHT && code != _URC_NO_REASON)
-    __terminate (header->terminateHandler);
+    __terminate (header->exc.terminateHandler);
 
 #ifdef _GLIBCXX_ATOMIC_BUILTINS_4
   if (__sync_sub_and_fetch (&header->referenceCount, 1) == 0)
     {
 #endif
-      if (header->exceptionDestructor)
-        header->exceptionDestructor (header + 1);
+      if (header->exc.exceptionDestructor)
+	header->exc.exceptionDestructor (header + 1);
 
       __cxa_free_exception (header + 1);
 #ifdef _GLIBCXX_ATOMIC_BUILTINS_4
@@ -66,23 +67,24 @@ __cxxabiv1::__cxa_throw (void *obj, std::type_info *tinfo,
 			 void (*dest) (void *))
 {
   // Definitely a primary.
-  __cxa_exception *header = __get_exception_header_from_obj (obj);
+  __cxa_refcounted_exception *header
+    = __get_refcounted_exception_header_from_obj (obj);
   header->referenceCount = 1;
-  header->exceptionType = tinfo;
-  header->exceptionDestructor = dest;
-  header->unexpectedHandler = __unexpected_handler;
-  header->terminateHandler = __terminate_handler;
-  __GXX_INIT_PRIMARY_EXCEPTION_CLASS(header->unwindHeader.exception_class);
-  header->unwindHeader.exception_cleanup = __gxx_exception_cleanup;
+  header->exc.exceptionType = tinfo;
+  header->exc.exceptionDestructor = dest;
+  header->exc.unexpectedHandler = __unexpected_handler;
+  header->exc.terminateHandler = __terminate_handler;
+  __GXX_INIT_PRIMARY_EXCEPTION_CLASS(header->exc.unwindHeader.exception_class);
+  header->exc.unwindHeader.exception_cleanup = __gxx_exception_cleanup;
 
 #ifdef _GLIBCXX_SJLJ_EXCEPTIONS
-  _Unwind_SjLj_RaiseException (&header->unwindHeader);
+  _Unwind_SjLj_RaiseException (&header->exc.unwindHeader);
 #else
-  _Unwind_RaiseException (&header->unwindHeader);
+  _Unwind_RaiseException (&header->exc.unwindHeader);
 #endif
 
   // Some sort of unwinding error.  Note that terminate is a handler.
-  __cxa_begin_catch (&header->unwindHeader);
+  __cxa_begin_catch (&header->exc.unwindHeader);
   std::terminate ();
 }
 
diff --git a/libstdc++-v3/libsupc++/unwind-cxx.h b/libstdc++-v3/libsupc++/unwind-cxx.h
index 3f6a765..3e2cf0f 100644
--- a/libstdc++-v3/libsupc++/unwind-cxx.h
+++ b/libstdc++-v3/libsupc++/unwind-cxx.h
@@ -1,5 +1,5 @@
 // -*- C++ -*- Exception handling and frame unwind runtime interface routines.
-// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 // Free Software Foundation, Inc.
 //
 // This file is part of GCC.
@@ -53,9 +53,6 @@ namespace __cxxabiv1
 
 struct __cxa_exception
 {
-  // Manage this header.
-  _Atomic_word referenceCount;
-
   // Manage the exception object itself.
   std::type_info *exceptionType;
   void (*exceptionDestructor)(void *); 
@@ -92,6 +89,14 @@ struct __cxa_exception
   _Unwind_Exception unwindHeader;
 };
 
+struct __cxa_refcounted_exception
+{
+  // Manage this header.
+  _Atomic_word referenceCount;
+  // __cxa_exception must be last, and no padding can be after it.
+  __cxa_exception exc;
+};
+
 // A dependent C++ exception object consists of a wrapper around an unwind
 // object header with additional C++ specific information, containing a pointer
 // to a primary exception object.
@@ -227,6 +232,21 @@ __get_exception_header_from_ue (_Unwind_Exception *exc)
   return reinterpret_cast<__cxa_exception *>(exc + 1) - 1;
 }
 
+// Acquire the C++ refcounted exception header from the C++ object.
+static inline __cxa_refcounted_exception *
+__get_refcounted_exception_header_from_obj (void *ptr)
+{
+  return reinterpret_cast<__cxa_refcounted_exception *>(ptr) - 1;
+}
+
+// Acquire the C++ refcounted exception header from the generic exception
+// header.
+static inline __cxa_refcounted_exception *
+__get_refcounted_exception_header_from_ue (_Unwind_Exception *exc)
+{
+  return reinterpret_cast<__cxa_refcounted_exception *>(exc + 1) - 1;
+}
+
 static inline __cxa_dependent_exception *
 __get_dependent_exception_from_ue (_Unwind_Exception *exc)
 {