1 files changed, 2 insertions, 6 deletions
diff --git a/Zend/zend_operators.c b/Zend/zend_operators.c
index 81f758e229..e420dd962e 100644
--- a/Zend/zend_operators.c
+++ b/Zend/zend_operators.c
@@ -2522,12 +2522,8 @@ ZEND_API char* ZEND_FASTCALL zend_str_tolower_dup_ex(const char *source, size_t
 				memcpy(res, source, p - (const unsigned char*)source);
 			}
 			r = (unsigned char*)p + (res - source);
-			while (p < end) {
-				*r = zend_tolower_ascii(*p);
-				p++;
-				r++;
-			}
-			*r = '\0';
+			zend_str_tolower_impl((char *)r, (const char*)p, end - p);
+			res[length] = '\0';
 			return res;
 		}
 		p++;