From 29c7ee4cd4621c9435574982884d9bc29ca02ae1 Mon Sep 17 00:00:00 2001
From: Alexandre Daubois <2144837+alexandre-daubois@users.noreply.github.com>
Date: Wed, 10 Sep 2025 16:52:31 +0200
Subject: [PATCH] Add a 1-char fastpath to `implode()` (#19276)

---
 ext/standard/string.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ext/standard/string.c b/ext/standard/string.c
index a5acb28ddb3..fffd796d94a 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -1026,7 +1026,11 @@ PHPAPI void php_implode(const zend_string *glue, HashTable *pieces, zval *return
 		}
 
 		cptr -= ZSTR_LEN(glue);
-		memcpy(cptr, ZSTR_VAL(glue), ZSTR_LEN(glue));
+		if (ZSTR_LEN(glue) == 1) {
+			*cptr = ZSTR_VAL(glue)[0];
+		} else {
+			memcpy(cptr, ZSTR_VAL(glue), ZSTR_LEN(glue));
+		}
 	}
 
 	free_alloca(strings, use_heap);