Gcc builtin review: strdup

[Ondřej Bílka]

Again there is missed optimization. Consider

int bar()
{
  return strdup("xyz");
}

This could be clearly expanded to

int bar()
{
  char *c = malloc (strlen ("xyz") + 1);
  memcpy (c, "xyz", strlen ("xyz") + 1);
}

One of consequences of this missed optimization is that in

int bar()
{
  char *c = strdup("xyz");
  return c[1];
}

gcc cannot determine that c[1] is y while it can in memcpy case.