PATCH: Factor __aeabi_atexit into its own object file

[Mark Mitchell <mark at codesourcery dot com>]

This patch moves __aeabi_atexit (a variant of __cxa_atexit required by
the ARM EABI) into its own object file.  At present, it was mixed in
with vec.o which contains vector construction/destruction routines.
As a result, an application with a global object with a destructor
(which therefore uses __aeabie_atexit) pulled in these vector
routines, and all the EH support that comes with that.

I also added an exception specification for __cxa_atexit in <cxxabi.h>
so that the compiler can tell that __aeabi_atexit does not need unwind
information.  (We should have exception specifications for more
declarations in <cxxabi.h>, but I didn't want to try to do all of that
in this patch.)

This seems near-obvious, but I'll give the libstdc++ maintainers a few
days to tell me if I'm being an idiot.  I've tested this patch against
a 4.2-based compiler for ARM EABI, and against x86_64-linux-gnu; on
the latter, the patch is nearly a no-op, since __aeabi_atexit is of
course not defined.

Thanks,

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713

2007-05-02  Mark Mitchell  <mark@codesourcery.com>

	* libsupc++/atexit_arm.cc: New file.
	* libsupc++/vec.cc (__aeabi_atexit): Remove.
	* libsupc++/cxxabi.h (__cxa_atexit): Add exception specification.
	* libsupc++/Makefile.am: Add atexit_arm.cc.
	* libsupc++/Makefile.in: Regenerated.

Index: libstdc++-v3/libsupc++/atexit_arm.cc
===================================================================
--- libstdc++-v3/libsupc++/atexit_arm.cc	(revision 0)
+++ libstdc++-v3/libsupc++/atexit_arm.cc	(revision 0)
@@ -0,0 +1,44 @@
+// Copyright (C) 2007 Free Software Foundation, Inc.
+//  
+// This file is part of GCC.
+//
+// GCC is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// GCC 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 General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING.  If not, write to
+// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+// Boston, MA 02110-1301, USA. 
+
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+
+#include <cxxabi.h>
+
+#if defined(__arm__) && defined(__ARM_EABI__)
+
+namespace __aeabiv1
+{
+  extern "C" int
+  __aeabi_atexit (void *object, 
+		  void (*destructor) (void *),
+		  void *dso_handle) throw ()
+  {
+    return abi::__cxa_atexit(destructor, object, dso_handle);
+  }
+} // namespace __aeabiv1
+
+#endif // defined(__arm__) && defined(__ARM_EABI__)
Index: libstdc++-v3/libsupc++/vec.cc
===================================================================
--- libstdc++-v3/libsupc++/vec.cc	(revision 170155)
+++ libstdc++-v3/libsupc++/vec.cc	(working copy)
@@ -499,14 +499,6 @@ namespace __aeabiv1
 			    2 * sizeof (std::size_t),
 			    /*destructor=*/NULL, dealloc);
   }
-  
-  extern "C" int
-  __aeabi_atexit (void *object, 
-		  void (*destructor) (void *),
-		  void *dso_handle)
-  {
-    return abi::__cxa_atexit(destructor, object, dso_handle);
-  }
 } // namespace __aeabiv1
 
 #endif // defined(__arm__) && defined(__ARM_EABI__)
Index: libstdc++-v3/libsupc++/cxxabi.h
===================================================================
--- libstdc++-v3/libsupc++/cxxabi.h	(revision 170155)
+++ libstdc++-v3/libsupc++/cxxabi.h	(working copy)
@@ -136,7 +136,7 @@ namespace __cxxabiv1
 
   // DSO destruction.
   int
-  __cxa_atexit(void (*)(void*), void*, void*);
+  __cxa_atexit(void (*)(void*), void*, void*) throw ();
 
   int
   __cxa_finalize(void*);
Index: libstdc++-v3/libsupc++/Makefile.am
===================================================================
--- libstdc++-v3/libsupc++/Makefile.am	(revision 170155)
+++ libstdc++-v3/libsupc++/Makefile.am	(working copy)
@@ -47,6 +47,7 @@ endif
 
 sources = \
 	array_type_info.cc \
+	atexit_arm.cc \
 	bad_cast.cc \
 	bad_typeid.cc \
 	class_type_info.cc \