[Bug tree-optimization/102542] New: [12 Regression] ICE Segmentation fault since r12-3876-g4a960d548b7d7d94

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102542

            Bug ID: 102542
           Summary: [12 Regression] ICE Segmentation fault since
                    r12-3876-g4a960d548b7d7d94
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: aldyh at gcc dot gnu.org
  Target Milestone: ---

The following crashes:

$ cat block-5.c
int a[200][200];
int b_j;


void b() {
  int i;
  b_j = 1;
  for (; b_j < 200; b_j++) {
    i = 0;
    for (; i < 200; i++)
      a[i][b_j] = a[i][b_j - 1];
  }
}

$ gcc block-5.c -c -fno-tree-ch -O3 -c
during GIMPLE pass: unrolljam
block-5.c: In function ‘b’:
block-5.c:5:6: internal compiler error: Segmentation fault
    5 | void b() {
      |      ^
0xf053da crash_signal
        /home/marxin/Programming/gcc/gcc/toplev.c:328
0x7ffff789979f ???
       
/usr/src/debug/glibc-2.34-1.2.x86_64/signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
0x107a35c tree_transform_and_unroll_loop(loop*, unsigned int, edge_def*,
tree_niter_desc*, void (*)(loop*, void*), void*)
        /home/marxin/Programming/gcc/gcc/tree-ssa-loop-manip.c:1425
0x1b6324b tree_loop_unroll_and_jam
        /home/marxin/Programming/gcc/gcc/gimple-loop-jam.c:590
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
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