Merge branch 'PHP-7.4'

* PHP-7.4:
  Fixed handling of references in nested data of objects with destructor

Author: dstogov

Zend/tests/gc_041.phpt

@@ -0,0 +1,35 @@
+--TEST--
+GC 041: Handling of references in nested data of objects with destructor
+--INI--
+zend.enable_gc = 1
+--FILE--
+<?php
+class ryat {
+	    var $ryat;
+        var $chtg;
+        var $nested;
+	    function __destruct() {
+	            $GLOBALS['x'] = $this;
+        }
+}
+$o = new ryat;
+$o->nested = [];
+$o->nested[] =& $o->nested;
+$o->ryat = $o;
+$x =& $o->chtg;
+unset($o);
+gc_collect_cycles();
+var_dump($x);
+?>
+--EXPECT--
+object(ryat)#1 (3) {
+  ["ryat"]=>
+  *RECURSION*
+  ["chtg"]=>
+  *RECURSION*
+  ["nested"]=>
+  &array(1) {
+    [0]=>
+    *RECURSION*
+  }
+}

Zend/zend_gc.c

@@ -1336,16 +1336,24 @@ static void gc_remove_nested_data_from_buffer(zend_refcounted *ref, gc_root_buff
 	zval *zv;
 
 tail_call:
-	if (root ||
-	    (GC_REF_ADDRESS(ref) != 0 &&
-	     GC_REF_CHECK_COLOR(ref, GC_BLACK))) {
-		GC_TRACE_REF(ref, "removing from buffer");
+	do {
 		if (root) {
+			GC_TRACE_REF(ref, "removing from buffer");
 			gc_remove_from_roots(root);
 			GC_REF_SET_INFO(ref, 0);
 			root = NULL;
-		} else {
+		} else if (GC_REF_ADDRESS(ref) != 0
+		 && GC_REF_CHECK_COLOR(ref, GC_BLACK)) {
+			GC_TRACE_REF(ref, "removing from buffer");
 			GC_REMOVE_FROM_BUFFER(ref);
+		} else if (GC_TYPE(ref) == IS_REFERENCE) {
+			if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
+				ref = Z_COUNTED(((zend_reference*)ref)->val);
+				goto tail_call;
+			}
+			return;
+		} else {
+			return;
 		}
 
 		if (GC_TYPE(ref) == IS_OBJECT) {
@@ -1379,12 +1387,6 @@ static void gc_remove_nested_data_from_buffer(zend_refcounted *ref, gc_root_buff
 			}
 		} else if (GC_TYPE(ref) == IS_ARRAY) {
 			ht = (zend_array*)ref;
-		} else if (GC_TYPE(ref) == IS_REFERENCE) {
-			if (Z_REFCOUNTED(((zend_reference*)ref)->val)) {
-				ref = Z_COUNTED(((zend_reference*)ref)->val);
-				goto tail_call;
-			}
-			return;
 		} else {
 			return;
 		}
@@ -1420,7 +1422,7 @@ static void gc_remove_nested_data_from_buffer(zend_refcounted *ref, gc_root_buff
 		}
 		ref = Z_COUNTED_P(zv);
 		goto tail_call;
-	}
+	} while (0);
 }
 
 ZEND_API int zend_gc_collect_cycles(void)