[Bug tree-optimization/98084] New: [11 Regression] ICE in error: non-integral type switch statement

[marxin at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98084

            Bug ID: 98084
           Summary: [11 Regression] ICE in error: non-integral type switch
                    statement
           Product: gcc
           Version: 11.0
            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
  Target Milestone: ---

It's since if-to-switch revision, reduced from systemd:

$ cat ~/Programming/testcases/json.i
enum {
  JSON_VARIANT_STRING,
  JSON_VARIANT_UNSIGNED,
  JSON_VARIANT_REAL,
  JSON_VARIANT_ARRAY,
  _JSON_VARIANT_TYPE_INVALID,
  _JSON_VARIANT_MAGIC_ZERO_UNSIGNED,
  _JSON_VARIANT_MAGIC_ZERO_REAL,
  _JSON_VARIANT_MAGIC_EMPTY_STRING,
  _JSON_VARIANT_MAGIC_EMPTY_ARRAY
} json_variant_type(int *v) {
  if (!v)
    return _JSON_VARIANT_TYPE_INVALID;
  if (v == (int *)_JSON_VARIANT_MAGIC_ZERO_UNSIGNED)
    return JSON_VARIANT_UNSIGNED;
  if (v == (int *)_JSON_VARIANT_MAGIC_ZERO_REAL)
    return JSON_VARIANT_REAL;
  if (v == (int *)_JSON_VARIANT_MAGIC_EMPTY_STRING)
    return JSON_VARIANT_STRING;
  if (v == (int *)_JSON_VARIANT_MAGIC_EMPTY_ARRAY)
    return JSON_VARIANT_ARRAY;
}

$ ./xgcc -B. ~/Programming/testcases/json.i -c -O2
/home/marxin/Programming/testcases/json.i: In function ‘json_variant_type’:
/home/marxin/Programming/testcases/json.i:22:1: error: non-integral type switch
statement
   22 | }
      | ^
int *
switch (v_2(D)) <default: <L16> [INV], case 0B: <L11> [INV], case 5B: <L12>
[INV], case 6B: <L13> [INV], case 7B: <L14> [INV], case 8B: <L15> [INV]>
during GIMPLE pass: iftoswitch
/home/marxin/Programming/testcases/json.i:22:1: internal compiler error:
verify_gimple failed
0xe365da verify_gimple_in_cfg(function*, bool)
        /home/marxin/Programming/gcc/gcc/tree-cfg.c:5467
0xd1075f execute_function_todo
        /home/marxin/Programming/gcc/gcc/passes.c:2042
0xd115ac do_per_function
        /home/marxin/Programming/gcc/gcc/passes.c:1687
0xd115ac execute_todo
        /home/marxin/Programming/gcc/gcc/passes.c:2096
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