[Bug tree-optimization/77646] [5/6/7 Regression] GCC Segfault with -O3

["trippels at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77646

--- Comment #3 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Or with creduce's rename-toks:

struct e {
  int (*f)();
  void (*g)();
} * c;
int a;
void *h();
typedef struct { struct e j; } k;
int l() { return a; }
const struct e b = {l};
void m() {
  k *d = h();
  d->j = b;
  c = (struct e *)d;
  struct e *i = c;
  if (i->f(c))
    while (i->f(c))
      i->g();
}