Fixed bug #77652

Author: nikic

NEWS

@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2019, PHP 7.2.17
 
+- Core:
+  . Fixed bug #77652 (Anonymous classes can lose their interface information).
+    (Nikita)
+
 - MySQLi:
   . Fixed bug #77597 (mysqli_fetch_field hangs scripts). (Nikita)
 

Zend/tests/bug77652.inc

@@ -0,0 +1,6 @@
+<?php
+return [
+  'I' => function() {
+    return new class implements I {};
+  },
+];

Zend/tests/bug77652.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Bug #77652: Anonymous classes can lose their interface information
+--FILE--
+<?php
+
+interface I {}
+require __DIR__ . '/bug77652.inc';
+$data = require __DIR__ . '/bug77652.inc';
+print_r(class_implements($data['I']()));
+
+?>
+--EXPECT--
+Array
+(
+    [I] => I
+)

Zend/zend_compile.c

@@ -6365,10 +6365,32 @@ void zend_compile_class_decl(zend_ast *ast) /* {{{ */
 		if (!zend_hash_exists(CG(class_table), lcname)) {
 			zend_hash_add_ptr(CG(class_table), lcname, ce);
 		} else {
-			/* this anonymous class has been included */
+			/* This anonymous class has been included, reuse the existing definition.
+			 * NB: This behavior is buggy, and this should always result in a separate
+			 * class declaration. However, until the problem of RTD key collisions is
+			 * solved, this gives a behavior close to what is expected. */
 			zval zv;
 			ZVAL_PTR(&zv, ce);
 			destroy_zend_class(&zv);
+			ce = zend_hash_find_ptr(CG(class_table), lcname);
+
+			/* Manually replicate emission of necessary inheritance opcodes here. We cannot
+			 * reuse the general code, as we only want to emit the opcodes, without modifying
+			 * the reused class definition. */
+			if (ce->ce_flags & ZEND_ACC_IMPLEMENT_TRAITS) {
+				zend_emit_op(NULL, ZEND_BIND_TRAITS, &declare_node, NULL);
+			}
+			if (implements_ast) {
+				zend_ast_list *iface_list = zend_ast_get_list(implements_ast);
+				uint32_t i;
+				for (i = 0; i < iface_list->children; i++) {
+					opline = zend_emit_op(NULL, ZEND_ADD_INTERFACE, &declare_node, NULL);
+					opline->op2_type = IS_CONST;
+					opline->op2.constant = zend_add_class_name_literal(CG(active_op_array),
+						zend_resolve_class_name_ast(iface_list->child[i]));
+				}
+				zend_emit_op(NULL, ZEND_VERIFY_ABSTRACT_CLASS, &declare_node, NULL);
+			}
 			return;
 		}
 	} else {