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From: "doko at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/58320] New: [4.7 / 4.8 / 4.9 Regression] code used in autoconf test fails with -O2, works with -O0
Date: Thu, 05 Sep 2013 10:06:00 -0000	[thread overview]
Message-ID: <bug-58320-4@http.gcc.gnu.org/bugzilla/> (raw)

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58320

            Bug ID: 58320
           Summary: [4.7 / 4.8 / 4.9 Regression] code used in autoconf
                    test fails with -O2, works with -O0
           Product: gcc
           Version: 4.7.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at gcc dot gnu.org

seen on arm-linux-gnueabihf, as part of an autoconf test in librep:

$ cat stack.c 
#include <stdlib.h>

void inner (char *foo) {
  char bar;
  exit (!(foo >= &bar));
}

void main () {
  char foo;
  inner (&foo);
}

$ gcc-4.6 -o conftest -O2 stack.c && ./conftest ; echo $?
0
$ gcc-4.7 -o conftest -O2 stack.c && ./conftest ; echo $?
1
$ gcc-4.8 -o conftest -O2 stack.c && ./conftest ; echo $?
1
$ gcc-4.8 -o conftest -O0 stack.c && ./conftest ; echo $?
0


             reply	other threads:[~2013-09-05 10:06 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-05 10:06 doko at gcc dot gnu.org [this message]
2013-09-05 10:36 ` [Bug target/58320] " rguenth at gcc dot gnu.org
2013-09-05 12:12 ` schwab@linux-m68k.org
2013-09-05 13:01 ` rguenth at gcc dot gnu.org

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