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* [Bug tree-optimization/102902] New: wrong code at -O3 on x86_64-linux-gnu (generated code hangs)
@ 2021-10-22 17:35 zhendong.su at inf dot ethz.ch
  2021-10-22 18:53 ` [Bug tree-optimization/102902] [12 Regression] " pinskia at gcc dot gnu.org
                   ` (10 more replies)
  0 siblings, 11 replies; 12+ messages in thread
From: zhendong.su at inf dot ethz.ch @ 2021-10-22 17:35 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102902

            Bug ID: 102902
           Summary: wrong code at -O3 on x86_64-linux-gnu (generated code
                    hangs)
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhendong.su at inf dot ethz.ch
  Target Milestone: ---

This appears to be a recent regression.

[575] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/12.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--prefix=/local/suz-local/software/local/gcc-trunk --enable-languages=c,c++
--disable-werror --enable-multilib --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 12.0.0 20211022 (experimental) [master r12-4624-gae5c540662e] (GCC) 
[576] % 
[576] % gcctk -O2 small.c; ./a.out
[577] % 
[577] % gcctk -O3 small.c
[578] % timeout -s 9 10 ./a.out
Killed
[579] % 
[579] % cat small.c
int printf (const char *, ...);
int a, b, c, d, e, f;
int main() {
  int g;
  short h = 1;
  for (; e < 2; e++) {
  L1:
    f = 1;
    while (b > 0 || a > 0) {
      g++;
      h++;
      printf("%d", g);
    }
  L2:
    if (!h && (!c || a))
      goto L1;
    if (c)
      goto L2;
  }
  return 0;
}

^ permalink raw reply	[flat|nested] 12+ messages in thread
end of thread, other threads:[~2022-04-04 12:59 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-10-22 17:35 [Bug tree-optimization/102902] New: wrong code at -O3 on x86_64-linux-gnu (generated code hangs) zhendong.su at inf dot ethz.ch
2021-10-22 18:53 ` [Bug tree-optimization/102902] [12 Regression] " pinskia at gcc dot gnu.org
2021-10-22 21:20 ` pinskia at gcc dot gnu.org
2021-10-25  8:44 ` [Bug tree-optimization/102902] [12 Regression] -O3 produces code that uses an uninitialized variable but originally was not used by r12-3876 marxin at gcc dot gnu.org
2021-10-25  8:45 ` marxin at gcc dot gnu.org
2021-10-25  8:57 ` marxin at gcc dot gnu.org
2021-10-25  8:58 ` rguenth at gcc dot gnu.org
2021-11-24  8:35 ` zhendong.su at inf dot ethz.ch
2021-11-24  8:44 ` pinskia at gcc dot gnu.org
2021-11-24  8:46 ` pinskia at gcc dot gnu.org
2022-01-17 13:09 ` rguenth at gcc dot gnu.org
2022-04-04 12:59 ` rguenth at gcc dot gnu.org

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