1  #include <string.h>
       2  #include "analyzer-decls.h"
       3  
       4  const char* test_literal (int x)
       5  {
       6    char *p = __builtin_strchr ("123", x); /* { dg-message "when '__builtin_strchr' returns non-NULL" } */
       7    if (p)
       8      {
       9        __analyzer_eval (*p == x); /* { dg-message "UNKNOWN" } */
      10        /* TODO: this ought to be TRUE, but it's unclear that it's
      11  	 worth stashing this constraint.  */
      12        *p = 'A'; /* { dg-warning "write to string literal" } */
      13      }
      14    return p;
      15  }
      16  
      17  void test_2 (const char *s, int c)
      18  {
      19    char *p = __builtin_strchr (s, c); /* { dg-message "when '__builtin_strchr' returns NULL"} */
      20    *p = 'A'; /* { dg-warning "dereference of NULL 'p'" "null deref" } */
      21  }
      22  
      23  void test_3 (const char *s, int c)
      24  {
      25    char *p = strchr (s, c); /* { dg-message "when 'strchr' returns NULL"} */
      26    *p = 'A'; /* { dg-warning "dereference of NULL 'p'" "null deref" } */
      27  }