modernc.org/cc@v1.0.1/testdata/gcc-6.3.0/gcc/testsuite/gcc.c-torture/compile/pr37976.c (about)

     1  void percent_x(int ch, char *p, char* ok_chars)
     2  {
     3    char *cp = ch == 'a' ? p : "";
     4    for (;*(cp += __builtin_strspn (cp, ok_chars));)
     5      ;
     6  }