fix #66872, invalid argument crashes gmp_testbit

Author: pierrejoye

ext/gmp/gmp.c

@@ -1511,25 +1511,23 @@ ZEND_FUNCTION(gmp_clrbit)
  Tests if bit is set in a */
 ZEND_FUNCTION(gmp_testbit)
 {
-zval **a_arg;
+zval *a_arg;
 long index;
-mpz_t *gmpnum_a;
+mpz_ptr gmpnum_a;
+gmp_temp_t temp_a;
 
-if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "Zl", &a_arg, &index) == FAILURE){
+if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "zl", &a_arg, &index) == FAILURE){
 return;
 }
 
-ZEND_FETCH_RESOURCE(gmpnum_a, mpz_t *, a_arg, -1, GMP_RESOURCE_NAME, le_gmp);
-
 if (index < 0) {
 php_error_docref(NULL TSRMLS_CC, E_WARNING, "Index must be greater than or equal to zero");
 RETURN_FALSE;
 }
 
-if (mpz_tstbit(*gmpnum_a, index)) {
-RETURN_TRUE;
-}
-RETURN_FALSE;
+FETCH_GMP_ZVAL(gmpnum_a, a_arg, temp_a);
+RETVAL_BOOL(mpz_tstbit(gmpnum_a, index));
+FREE_GMP_TEMP(temp_a);
 }
 /* }}} */