[Bug tree-optimization/115199] New: [15 regression] gettext (libtextstyle) testsuite miscompiled

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115199

            Bug ID: 115199
           Summary: [15 regression] gettext (libtextstyle) testsuite
                    miscompiled
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sjames at gcc dot gnu.org
                CC: kacper.slominski72 at gmail dot com
  Target Milestone: ---

This originally came out with gettext (libtextstyle)'s testsuite being
miscompiled with a single test failing.

Kacper Słomiński (qookie) did all the separation and reduction work.

We both tidied it up together a bit more after and hopefully we didn't do it
too far:
```
struct b {
  char *volatile c;
} *d() {
  char *e;
  struct b *b = __builtin_malloc(sizeof(b));
  void *f = __builtin_malloc(1);

  e = __builtin_memcpy(f, "z", 1);
  b->c = e;
  return b;
}

int main() {
  struct b b = *d();
  if (b.c[0] != 'z')
    __builtin_abort();
}
```