Gcc builtin review: strstr, strcasestr, memmem

[Ondřej Bílka]

A gcc does little optimizations, just constant arguments.

And why gcc doesnt optimize memmem as arguments are constant and with
size 1 needle it could use memchr?

#include <string.h>
int foo(char *x)
{
  return memmem ("tauhtatu", 4, "f", 1);
}