date: Fix typo in condition in date_period_init_iso8601_string()

Now the address is being checked instead of the value, but I believe the
value should be checked against 0, not the pointer against NULL.

Closes GH-22253.

Author: ndossche

NEWS

@@ -6,6 +6,10 @@ PHP                                                                        NEWS
   . Fixed issues with oversized allocations and signed overflow in bcround()
     and BcMath\Number::round(). (edorian)
 
+- Date:
+  . Fix incorrect recurrence check of DatePeriod::createFromISO8601String().
+    (ndossche)
+
 - GD:
   . Fixed bug GH-22121 (Double free in gdImageSetStyle() after
     overflow-triggered early return). (iliaal)

ext/date/php_date.c

@@ -5125,7 +5125,7 @@ static bool date_period_init_iso8601_string(php_period_obj *dpobj, zend_class_en
 		zend_string_release(func);
 		return false;
 	}
-	if (dpobj->end == NULL && recurrences == 0) {
+	if (dpobj->end == NULL && *recurrences == 0) {
 		zend_string *func = get_active_function_or_method_name();
 		zend_throw_exception_ex(date_ce_date_malformed_period_string_exception, 0, "%s(): ISO interval must contain an end date or a recurrence count, \"%s\" given", ZSTR_VAL(func), isostr);
 		zend_string_release(func);

ext/date/tests/date_period_bad_iso_format.phpt

@@ -50,5 +50,5 @@ DateMalformedPeriodStringException: DatePeriod::__construct(): ISO interval must
 DateMalformedPeriodStringException: DatePeriod::createFromISO8601String(): ISO interval must contain an interval, "R4/2012-07-01T00:00:00Z" given
 
 Deprecated: Calling DatePeriod::__construct(string $isostr, int $options = 0) is deprecated, use DatePeriod::createFromISO8601String() instead in %s on line %d
-DateMalformedPeriodStringException: DatePeriod::__construct(): Recurrence count must be greater or equal to 1 and lower than %d
-DateMalformedPeriodStringException: DatePeriod::createFromISO8601String(): Recurrence count must be greater or equal to 1 and lower than %d
+DateMalformedPeriodStringException: DatePeriod::__construct(): ISO interval must contain an end date or a recurrence count, "2012-07-01T00:00:00Z/P7D" given
+DateMalformedPeriodStringException: DatePeriod::createFromISO8601String(): ISO interval must contain an end date or a recurrence count, "2012-07-01T00:00:00Z/P7D" given