[Bug c/105149] New: [9/10/11/12 Regression] ICE in verify_ssa, at tree-ssa.cc:1211

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105149

            Bug ID: 105149
           Summary: [9/10/11/12 Regression] ICE in verify_ssa, at
                    tree-ssa.cc:1211
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

Affects versions down to r6, at -O1+ :
(gcc configured with --enable-checking=yes)


$ cat z1.c
#include <stdarg.h>
void foo (int size, ...)
{
  struct {} d;
  va_list ap;
  d = va_arg (ap, typeof(d)()) ();
}


$ gcc-5 -c z1.c -O2
$ gcc-12-20220403 -c z1.c
$
$ gcc-12-20220403 -c z1.c -O2
z1.c: In function 'foo':
z1.c:7:1: error: virtual definition of statement not up to date
    7 | }
      | ^
D.1987 = _1;
during GIMPLE pass: ssa
z1.c:7:1: internal compiler error: verify_ssa failed
0x10a33db verify_ssa(bool, bool)
        ../../gcc/tree-ssa.cc:1211
0xd01ea7 execute_function_todo
        ../../gcc/passes.cc:2092
0xd027f2 execute_todo
        ../../gcc/passes.cc:2139