Fix GH-10497: Allow const obj->prop = value

Zend/tests/gh10497.phpt

@@ -0,0 +1,39 @@
+--TEST--
+GH-10497: Allow direct modification of object stored in a constant
+--FILE--
+<?php
+const a = new stdClass;
+a->b = 42;
+var_dump(a->b);
+
+const obj = new stdClass;
+obj->foo = 'bar';
+obj->baz = 123;
+var_dump(obj->foo, obj->baz);
+
+const nested = new stdClass;
+nested->inner = new stdClass;
+nested->inner->value = 999;
+var_dump(nested->inner->value);
+
+const readTest = new stdClass;
+readTest->prop = 'test';
+echo readTest->prop . "\n";
+
+var_dump(isset(readTest->prop));
+var_dump(empty(readTest->missing));
+
+const modTest = new stdClass;
+modTest->val = 1;
+modTest->val = 2;
+var_dump(modTest->val);
+?>
+--EXPECT--
+int(42)
+string(3) "bar"
+int(123)
+int(999)
+test
+bool(true)
+bool(true)
+int(2)

Zend/tests/gh12102_3.phpt

@@ -5,11 +5,8 @@ GH-12102: Incorrect "Cannot use temporary expression in write context" error for
 
 function test() {
     byVal(C[0]);
-    try {
-        byRef(C[0]);
-    } catch (Error $e) {
-        echo $e->getMessage(), "\n";
-    }
+    byRef(C[0]);
+    var_dump(C);
 }
 
 /* Intentionally declared after test() to avoid compile-time checking of ref args. */
@@ -21,6 +18,7 @@ function byVal($arg) {
 }
 
 function byRef(&$arg) {
+    $arg = 'modified';
     var_dump($arg);
 }
 
@@ -29,4 +27,8 @@ test('y');
 ?>
 --EXPECT--
 string(3) "foo"
-Cannot use temporary expression in write context
+string(8) "modified"
+array(1) {
+  [0]=>
+  string(3) "foo"
+}

Zend/zend_compile.c

@@ -11101,7 +11101,7 @@ static void zend_compile_array(znode *result, zend_ast *ast) /* {{{ */
 }
 /* }}} */
 
-static void zend_compile_const(znode *result, const zend_ast *ast) /* {{{ */
+static zend_op *zend_compile_const_inner(znode *result, const zend_ast *ast, bool use_tmp) /* {{{ */
 {
 	zend_ast *name_ast = ast->child[0];
 
@@ -11125,17 +11125,21 @@ static void zend_compile_const(znode *result, const zend_ast *ast) /* {{{ */
 			result->op_type = IS_CONST;
 			ZVAL_LONG(&result->u.constant, Z_LVAL_P(zend_ast_get_zval(last->child[0])));
 			zend_string_release_ex(resolved_name, 0);
-			return;
+			return NULL;
 		}
 	}
 
 	if (zend_try_ct_eval_const(&result->u.constant, resolved_name, is_fully_qualified)) {
 		result->op_type = IS_CONST;
 		zend_string_release_ex(resolved_name, 0);
-		return;
+		return NULL;
 	}
 
-	opline = zend_emit_op_tmp(result, ZEND_FETCH_CONSTANT, NULL, NULL);
+	if (use_tmp) {
+		opline = zend_emit_op_tmp(result, ZEND_FETCH_CONSTANT, NULL, NULL);
+	} else {
+		opline = zend_emit_op(result, ZEND_FETCH_CONSTANT, NULL, NULL);
+	}
 	opline->op2_type = IS_CONST;
 
 	if (is_fully_qualified || !FC(current_namespace)) {
@@ -11148,6 +11152,13 @@ static void zend_compile_const(znode *result, const zend_ast *ast) /* {{{ */
 			resolved_name, true);
 	}
 	opline->extended_value = zend_alloc_cache_slot();
+	return opline;
+}
+/* }}} */
+
+static void zend_compile_const(znode *result, const zend_ast *ast) /* {{{ */
+{
+	zend_compile_const_inner(result, ast, true);
 }
 /* }}} */
 
@@ -12085,6 +12096,8 @@ static zend_op *zend_compile_var_inner(znode *result, zend_ast *ast, uint32_t ty
 		case ZEND_AST_ZNODE:
 			*result = *zend_ast_get_znode(ast);
 			return NULL;
+		case ZEND_AST_CONST:
+			return zend_compile_const_inner(result, ast, false);
 		default:
 			if (type == BP_VAR_W || type == BP_VAR_RW || type == BP_VAR_UNSET) {
 				zend_error_noreturn(E_COMPILE_ERROR,