Fix bug #68775

Author: nikic

Zend/tests/bug68775.phpt

@@ -0,0 +1,19 @@
+--TEST--
+Bug #68775: yield in a function argument crashes or loops indefinitely
+--FILE--
+<?php
+
+function a($x) {
+    var_dump($x);
+}
+
+function gen() {
+     a(yield);
+}
+
+$g = gen();
+$g->send(1);
+
+?>
+--EXPECT--
+int(1)

Zend/zend_generators.c

@@ -303,8 +303,8 @@ ZEND_API void zend_generator_resume(zend_generator *generator) /* {{{ */
 		zend_execute_data *original_execute_data = EG(current_execute_data);
 		zend_class_entry *original_scope = EG(scope);
 		zend_vm_stack original_stack = EG(vm_stack);
-
 		original_stack->top = EG(vm_stack_top);
+
 		/* Set executor globals */
 		EG(current_execute_data) = generator->execute_data;
 		EG(scope) = generator->execute_data->func->common.scope;
@@ -314,8 +314,7 @@ ZEND_API void zend_generator_resume(zend_generator *generator) /* {{{ */
 
 		/* We want the backtrace to look as if the generator function was
 		 * called from whatever method we are current running (e.g. next()).
-		 * So we have to link generator call frame with caller call frames */
-
+		 * So we have to link generator call frame with caller call frame. */
 		generator->execute_data->prev_execute_data = original_execute_data;
 
 		/* Resume execution */
@@ -329,6 +328,7 @@ ZEND_API void zend_generator_resume(zend_generator *generator) /* {{{ */
 		}
 
 		/* Restore executor globals */
+		generator->stack->top = EG(vm_stack_top);
 		EG(current_execute_data) = original_execute_data;
 		EG(scope) = original_scope;
 		EG(vm_stack_top) = original_stack->top;