[Bug rtl-optimization/58034] New: glibc nptl/tst-cleanup2 fail due to scheduling

[amodra at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58034

            Bug ID: 58034
           Summary: glibc nptl/tst-cleanup2 fail due to scheduling
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: amodra at gmail dot com

Created attachment 30575
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30575&action=edit
preprocessed test case

nprl/tst-cleanup2 fails when compiled with -O2 -mcpu=power6 due to sched1
moving an assignment to a REG over code that traps.

The relevant test case source:

  if (setjmp (jmpbuf))
    {
      puts ("Exiting main...");
      return 0;
    }

  sprintf (p, "This should segv\n");

  return 1;
}

The sprintf is optimised to three loads and stores.  The problem occurs due to
the assignment of 1 to the REG holding the function return value being
scheduled before the sprintf expansion.