intl: Fix memory leak on error in locale_filter_matches()

Closes phpGH-20207.

Author: ndossche

NEWS

@@ -23,6 +23,9 @@ PHP                                                                        NEWS
   . Fixed bug GH-20070 (Return type violation in imagefilter when an invalid
     filter is provided). (Girgias)
 
+- Intl:
+  . Fix memory leak on error in locale_filter_matches(). (nielsdos)
+
 - LibXML:
   . Fix not thread safe schema/relaxng calls. (SpencerMalone, nielsdos)
 

ext/intl/locale/locale_methods.c

@@ -1301,6 +1301,7 @@ PHP_FUNCTION(locale_filter_matches)
 		/* canonicalize lang_tag */
 		can_lang_tag = get_icu_value_internal( lang_tag , LOC_CANONICALIZE_TAG , &result ,  0);
 		if( result <=0) {
+			zend_string_release_ex( can_loc_range, false );
 			intl_error_set( NULL, status,
 				"locale_filter_matches : unable to canonicalize lang_tag" , 0 );
 			RETURN_FALSE;