[Bug c/126876] [17 regression] ice in ssa_range_in_phi

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126876

--- Comment #2 from David Binderman <dcb314 at hotmail dot com> ---
Reduced code seems to be:

unsigned char *S_parser_feed_eol;
char S_parser_feed_end;
void S_parser_feed(unsigned char *buffer) {
  while (buffer) {
    int chunk_len;
    for (; S_parser_feed_eol;)
      chunk_len = S_parser_feed_eol - buffer;
    buffer += chunk_len;
    if (S_parser_feed_end)
      if (*buffer)
        buffer++;
  }
}