Re: optimization/5878: gcc 3.1 breaks on C code generated by the Mercury compiler

Re: optimization/5878: gcc 3.1 breaks on C code generated by the Mercury compiler

[rth]

Synopsis: gcc 3.1 breaks on C code generated by the Mercury compiler

State-Changed-From-To: open->closed
State-Changed-By: rth
State-Changed-When: Tue Mar 12 21:43:38 2002
State-Changed-Why:
    http://gcc.gnu.org/ml/gcc-patches/2002-03/msg00746.html

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5878

Re: optimization/5878: gcc 3.1 breaks on C code generated by the Mercury compiler

[rth]

Synopsis: gcc 3.1 breaks on C code generated by the Mercury compiler

Responsible-Changed-From-To: unassigned->rth
Responsible-Changed-By: rth
Responsible-Changed-When: Tue Mar 12 21:16:08 2002
Responsible-Changed-Why:
    .

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5878

optimization/5878: gcc 3.1 breaks on C code generated by the Mercury compiler

[Fergus Henderson]

>Number:         5878
>Category:       optimization
>Synopsis:       gcc 3.1 breaks on C code generated by the Mercury compiler
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    unassigned
>State:          open
>Class:          ice-on-legal-code
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 07 19:36:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Fergus Henderson <fjh@cs.mu.oz.au>
>Release:        3.1 20020304 (prerelease)
>Organization:
>Environment:
Reading specs from /tmp/fjh/install/lib/gcc-lib/i686-pc-linux-gnu/3.1/specs
Configured with: configure --prefix=/tmp/fjh/install
Thread model: single
gcc version 3.1 20020304 (prerelease)
>Description:
gcc 3.1 gets an internal error when compiling the attached
file with optimization enabled.
This is a regression from gcc 2.95.3.

The output is:
bash$ gcc -O mercury-gcc3.1.c
mercury-gcc3.1.c: In function `f':
mercury-gcc3.1.c:22: Internal compiler error in verify_local_live_at_start, at flow.c:606
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.           
>How-To-Repeat:
Compile the attached file with `gcc -c -O',
e.g. `gcc -c -O bug.c'.

void *dummy (void *);
register void *reg __asm__ ("ebx");

void
f (void)
{
  goto *dummy (&&foo);
  for (;;)
    {
    foo:
      (reg) = (void *) 1;

      if (!reg)
        goto baz;

      reg = (&&bar);
    }

bar:
baz:
  reg = 0;
}
>Fix:
A work-around is to compile without `-O'.
>Release-Note:
>Audit-Trail:
>Unformatted:
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