diff --git a/ext/opcache/jit/zend_jit_helpers.c b/ext/opcache/jit/zend_jit_helpers.c
index 563a9b5db50..5f435e328e0 100644
--- a/ext/opcache/jit/zend_jit_helpers.c
+++ b/ext/opcache/jit/zend_jit_helpers.c
@@ -1100,6 +1100,9 @@ static zend_string* ZEND_FASTCALL zend_jit_fetch_dim_str_r_helper(zend_string *s
 	} else {
 		offset = Z_LVAL_P(dim);
 	}
+	if (UNEXPECTED(EG(exception) != NULL)) {
+		return ZSTR_EMPTY_ALLOC();
+	}
 	return zend_jit_fetch_dim_str_offset(str, offset);
 }
 
diff --git a/ext/opcache/tests/jit/gh12723-A.phpt b/ext/opcache/tests/jit/gh12723-A.phpt
new file mode 100644
index 00000000000..f30453e8c0a
--- /dev/null
+++ b/ext/opcache/tests/jit/gh12723-A.phpt
@@ -0,0 +1,20 @@
+--TEST--
+GH-12723: Function JIT emits "Uninitialized string offset" warning at the same time as invalid offset Error
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+--FILE--
+<?php
+
+$container = '';
+$dimension = [];
+
+try {
+    var_dump($container[$dimension]);
+} catch (\Throwable $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+Cannot access offset of type array on string