[Bug target/65032] [5 Regression] ICE in reload_combine_note_use, at postreload.c:1556 on i686-linux-gnu

["trippels at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65032

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
                 CC|                            |trippels at gcc dot gnu.org

--- Comment #3 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
I cannot reproduce the original issue.

For the testcase from comment 2:

markus@x4 tmp % g++ -c -w -m32 -Os -std=gnu++11 -fPIC -fstack-protector-strong
-fno-strict-aliasing -fno-exceptions  -fomit-frame-pointer testc.ii

In file included from
/builddir/build/BUILD/firefox-36.0/mozilla-release/objdir/dom/media/ogg/Unified_cpp_dom_media_ogg0.cpp:20:0:
/builddir/build/BUILD/firefox-36.0/mozilla-release/dom/media/ogg/OggReader.cpp:
In member function ‘nsresult mozilla::OggReader::DecodeVorbis(ogg_packet*)’:
/builddir/build/BUILD/firefox-36.0/mozilla-release/dom/media/ogg/OggReader.cpp:562:1:
internal compiler error: in reload_combine_note_use, at postreload.c:1556
0xbf4b3a reload_combine_note_use
        ../../gcc/gcc/postreload.c:1556
0xbf48bf reload_combine_note_use
        ../../gcc/gcc/postreload.c:1643
0xbf65f3 reload_combine
        ../../gcc/gcc/postreload.c:1423
0xbf76e0 reload_cse_regs
        ../../gcc/gcc/postreload.c:95
0xbf76e0 execute
        ../../gcc/gcc/postreload.c:2367
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions

Reducing...
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From: "jan.kratochvil at redhat dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/65168] New: diagnostic: missing: reference cannot be bound to dereferenced null pointer
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https://gcc.gnu.org/bugzilla/show_bug.cgi?ide168

            Bug ID: 65168
           Summary: diagnostic: missing: reference cannot be bound to
                    dereferenced null pointer
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jan.kratochvil at redhat dot com
            Target: x86_64-linux-gnu

int main() {
  int *p=static_cast<int *>(0),&r=*p;
  return !&r;
}

-Wall

g++ (GCC) 5.0.0 20150221 (experimental)
<nothing>

clang++ (clang-3.5.0-6.fc21.x86_64):
ref.C:3:12: warning: reference cannot be bound to dereferenced null pointer in
well-defined C++ code; pointer may be assumed to always convert to true
[-Wundefined-bool-conversion]

I have no idea if it can be miscompiled by either compiler.  Still I find
useful to be notified I write non-conforming C++ code.