[Bug tree-optimization/95487] New: ICE: verify_gimple failed (error: invalid vector types in nop conversion) with -O3 -march=skylake-avx512

[vsevolod.livinskij at frtk dot ru]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95487

            Bug ID: 95487
           Summary: ICE: verify_gimple failed (error: invalid vector types
                    in nop conversion) with -O3 -march=skylake-avx512
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: vsevolod.livinskij at frtk dot ru
  Target Milestone: ---

Error:
>$ g++ -O3 -march=skylake-avx512 -c func.cpp
func.cpp: In function ‘void h()’:
func.cpp:7:6: error: invalid vector types in nop conversion
    7 | void h() {
      |      ^
char
vector(32) unsigned char
stmp_117 = (char) stmp_116;
func.cpp:7:6: error: invalid vector types in nop conversion
char
vector(32) unsigned char
stmp_120 = (char) stmp_119;
during GIMPLE pass: vect
func.cpp:7:6: internal compiler error: verify_gimple failed
0x1141df1 verify_gimple_in_cfg(function*, bool)
        /gcc/tree-cfg.c:5461
0x10152af execute_function_todo
        /gcc/passes.c:1985
0x101608e execute_todo
        /gcc/passes.c:2039

Reproducer:
int a;
bool d;
char e;
extern short f[];
extern int g[];
short j;
void h() {
  for (short b = j; b < 0; b += 2) {
    f[b] = 0;
    if (d) {
      for (char c = 0; c < a; c += 3)
        e = 0;
      g[b] = 0;
    }
  }
}

GCC version:
11.0.0 (4b68cb38ddca37a14a6f2f43de3a6d396ee1bc79)

bug 92741 might be related