Fix memory leak on unknown named param in iterator unpack

Author: nikic

Zend/tests/named_params/unknown_named_param.phpt

@@ -27,6 +27,12 @@ try {
     echo $e->getMessage(), "\n";
 }
 
+try {
+    test(...new ArrayIterator(['unknown' => 42]));
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
 try {
     test2(a: 42);
 } catch (Error $e) {
@@ -38,3 +44,4 @@ try {
 Unknown named parameter $b
 Unknown named parameter $b
 Unknown named parameter $b
+Unknown named parameter $unknown

Zend/zend_vm_def.h

@@ -5107,6 +5107,7 @@ ZEND_VM_C_LABEL(send_again):
 					have_named_params = 1;
 					top = zend_handle_named_arg(&EX(call), name, &arg_num, cache_slot);
 					if (UNEXPECTED(!top)) {
+						zend_string_release(name);
 						break;
 					}
 

Zend/zend_vm_execute.h

@@ -1995,6 +1995,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_SEND_UNPACK_SPEC_HANDLER(ZEND_
 					have_named_params = 1;
 					top = zend_handle_named_arg(&EX(call), name, &arg_num, cache_slot);
 					if (UNEXPECTED(!top)) {
+						zend_string_release(name);
 						break;
 					}