[Bug libstdc++/51135] New: SIGSEGV during exception cleanup on win32

[Bug libstdc++/51135] New: SIGSEGV during exception cleanup on win32

[gurnec-bugz at gis dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

             Bug #: 51135
           Summary: SIGSEGV during exception cleanup on win32
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gurnec-bugz@gis.net


It looks like __thiscall is now the default calling convention for member
functions (where possible) for win32 targets. This seems to have broken
exception cleanup. 

This seg faults when executed (and compiled by mingw-32):

===============
struct except {
  virtual ~except() {}
};

int main() {
  try {
    throw except();
  } catch(except) {
  }
}
===============

The seg fault occurs after the catch block is exited, and except::~except() is
called by the runtime. I think __gxx_exception_cleanup (in
libstdc++-v3/libsupc++/eh_throw.cc) is still trying to call except::~except()
using the old calling convention, resulting in a seg fault on any access to
'this'.

-Chris

[Bug libstdc++/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.7.0

[Bug libstdc++/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |cgf at gcc dot gnu.org,
                   |                            |dave.korn.cygwin at gmail
                   |                            |dot com, ktietz at gcc dot
                   |                            |gnu.org

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-12-05 14:52:58 UTC ---
This badly requires a target maintainer.

[Bug libstdc++/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[davek at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Dave Korn <davek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |davek at gcc dot gnu.org

--- Comment #2 from Dave Korn <davek at gcc dot gnu.org> 2011-12-05 15:10:54 UTC ---
Doesn't reproduce on Cygwin, and I don't have a current mingw cross compiler
handy.  It would be best if Kai can look at this as I'm up to my neck in ada at
the moment, if he hasn't found time in the next four or five days I'll try and
investigate.

[Bug libstdc++/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Kai Tietz <ktietz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-12-05
     Ever Confirmed|0                           |1

--- Comment #3 from Kai Tietz <ktietz at gcc dot gnu.org> 2011-12-05 15:17:34 UTC ---
Well, this seems to be caused by member exceptionDestructor in __cxa_exception
structure.  As a destructor has also __thiscall convention, we need to specify
it here for 32-bit Windows target.

I am just about to test a patch for it.

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |mingw32
           Priority|P3                          |P1
          Component|libstdc++                   |target

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

--- Comment #4 from Kai Tietz <ktietz at gcc dot gnu.org> 2011-12-12 13:29:14 UTC ---
Author: ktietz
Date: Mon Dec 12 13:29:10 2011
New Revision: 182238

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182238
Log:
Correct bug-number in ChangeLog.

        PR libstdc++/51135
        * libsupc++/cxxabi.h (__cxxabi_dtor_type): New type.
        (__cxa_throw): Use it for destructor-argument.
        * libsupc++/eh_throw.cc (__cxa_throw): Likewise.
        * libsupc++/unwind-cxx.h (__cxa_exception): Change type of member
        exceptionDestructor to __cxxabi_dtor_type.
        * config/os/mingw32-w64/os_defines.h (_GLIBCXX_USE_THISCALL_ON_DTOR):
        Define.
        (__cxa_dtor_type): Declare target secific type variant.
        * config/os/mingw32/os_defines.h: Likewise.

Modified:
    trunk/libstdc++-v3/ChangeLog

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Kai Tietz <ktietz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED

--- Comment #5 from Kai Tietz <ktietz at gcc dot gnu.org> 2011-12-12 13:31:16 UTC ---
Fixed at revision 182237.

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[paolo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

--- Comment #6 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> 2011-12-12 17:34:24 UTC ---
Author: paolo
Date: Mon Dec 12 17:34:19 2011
New Revision: 182250

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182250
Log:
2011-12-12  Paolo Carlini  <paolo.carlini@oracle.com>

    Revert:
    2011-12-12  Kai Tietz  <ktietz@redhat.com>

    PR libstdc++/51135
    * libsupc++/cxxabi.h (__cxa_dtor_type): New type.
    (__cxa_throw): Use it for destructor-argument.
    * libsupc++/eh_throw.cc (__cxa_throw): Likewise.
    * libsupc++/unwind-cxx.h (__cxa_exception): Change type of member
    exceptionDestructor to __cxa_dtor_type.
    * config/os/mingw32-w64/os_defines.h (_GLIBCXX_USE_THISCALL_ON_DTOR):
    Define.
    (__cxa_dtor_type): Declare target secific type variant.
    * config/os/mingw32/os_defines.h: Likewise.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/config/os/mingw32-w64/os_defines.h
    trunk/libstdc++-v3/config/os/mingw32/os_defines.h
    trunk/libstdc++-v3/libsupc++/cxxabi.h
    trunk/libstdc++-v3/libsupc++/eh_throw.cc
    trunk/libstdc++-v3/libsupc++/unwind-cxx.h

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
         Resolution|FIXED                       |

--- Comment #7 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-12-12 17:38:08 UTC ---
Patch reverted.

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

--- Comment #8 from Kai Tietz <ktietz at gcc dot gnu.org> 2011-12-16 18:43:11 UTC ---
Author: ktietz
Date: Fri Dec 16 18:43:06 2011
New Revision: 182410

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182410
Log:
        PR libstdc++/51135
        * libsupc++/unwind-cxx.h (__cxa_exception): Mark
        exceptionDestructor by _GLIBCXX_CDTOR_CALLABI.
        * libsupc++/eh_throw.cc (__cxa_throw): Mark destructor
        function argument by _GLIBCXX_CDTOR_CALLABI.
        * libsupc++/cxxabi.h (__cxa_throw): Likewise.
        (_GLIBCXX_CDTOR_CALLABI): Add empty default
        definition.
        * config/os/mingw32-w64/os_defines.h (_GLIBCXX_CDTOR_CALLABI): Define
        for IA-32 target as __thiscall.
        * config/os/mingw32/os_defines.h (_GLIBCXX_CDTOR_CALLABI): Likewise.


Modified:
    trunk/libstdc++-v3/config/os/mingw32-w64/os_defines.h
    trunk/libstdc++-v3/config/os/mingw32/os_defines.h
    trunk/libstdc++-v3/libsupc++/cxxabi.h
    trunk/libstdc++-v3/libsupc++/eh_throw.cc
    trunk/libstdc++-v3/libsupc++/unwind-cxx.h

[Bug target/51135] [4.7 Regression] SIGSEGV during exception cleanup on win32

[ktietz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51135

Kai Tietz <ktietz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|REOPENED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #9 from Kai Tietz <ktietz at gcc dot gnu.org> 2011-12-16 18:46:36 UTC ---
Fixed at revision 182410.