[Bug c/109331] New: ice: definition in block 7 does not dominate use in block 8

[Bug c/109331] New: ice: definition in block 7 does not dominate use in block 8

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109331

            Bug ID: 109331
           Summary: ice: definition in block 7 does not dominate use in
                    block 8
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

This reduced C code:

ustol_dpp;
ustol(flags) {
  char *s;
  if (s)
    flags |= 3;
  switch (flags & 3)
  case 3:
    while (*s)
    case '+':
      ++s;
  if (flags)
    ustol_dpp = s;
}

when compiled by this morning's trunk gcc and flag -O1, does this:

$ ~/gcc/results/bin/gcc -c -w -O1 bug904.c
bug904.c: In function ‘ustol’:
bug904.c:2:1: error: definition in block 7 does not dominate use in block 8
    2 | ustol(flags) {
      | ^~~~~
for SSA_NAME: s_8 in statement:
s.0_3 = (long int) s_8;
during GIMPLE pass: forwprop
bug904.c:2:1: internal compiler error: verify_ssa failed
0x110bc49 verify_ssa(bool, bool)
        ../../trunk.year/gcc/tree-ssa.cc:1211

This was fine with yesterday's compiler:

$ ~/gcc/results.20230328/bin/gcc -c -w -O1 bug904.c
$ 

Git range is g:304c7d44a2212e6f to g:36330e2e95564a36, which is 35 commits.

[Bug tree-optimization/109331] ice: definition in block 7 does not dominate use in block 8

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109331

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |tree-optimization
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot gnu.org
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2023-03-29

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Mine.

[Bug tree-optimization/109331] ice: definition in block 7 does not dominate use in block 8

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109331

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:86efc490ab86bfa00720479b4714da23cd7df797

commit r13-6928-g86efc490ab86bfa00720479b4714da23cd7df797
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Mar 29 11:59:16 2023 +0200

    tree-optimization/109331 - make sure to clean up the CFG after forwprop

    When forwprop discovers unreachable code or makes decisions based
    on unreachable edges make sure to cleanup the CFG since otherwise
    SSA form can become invalid.

            PR tree-optimization/109331
            * tree-ssa-forwprop.cc (pass_forwprop::execute): When we
            discover a taken edge make sure to cleanup the CFG.

            * gcc.dg/torture/pr109331.c: New testcase.

[Bug tree-optimization/109331] ice: definition in block 7 does not dominate use in block 8

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109331

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.

[Bug tree-optimization/109331] [13 Regression] ice: definition in block 7 does not dominate use in block 8

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109331

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
   Target Milestone|---                         |13.0
            Summary|ice: definition in block 7  |[13 Regression] ice:
                   |does not dominate use in    |definition in block 7 does
                   |block 8                     |not dominate use in block 8