Index: Python/symtable.c
===================================================================
--- Python/symtable.c	(revision 68142)
+++ Python/symtable.c	(working copy)
@@ -22,7 +22,12 @@
 #define RETURN_VAL_IN_GENERATOR \
     "'return' with argument inside generator"
 
+#define RETURN_OUTSIDE_FUNCTION \
+    "'return' outside function"
 
+#define YIELD_OUTSIDE_FUNCTION \
+    "'yield' outside function"
+
 static PySTEntryObject *
 ste_new(struct symtable *st, identifier name, _Py_block_ty block,
 	      void *key, int lineno)
@@ -1063,6 +1068,12 @@
 		break;
 	}
         case Return_kind:
+		if (st->st_cur->ste_type != FunctionBlock) {
+			PyErr_SetString(PyExc_SyntaxError,
+				RETURN_OUTSIDE_FUNCTION);
+		        PyErr_SyntaxLocation(st->st_filename,
+			             s->lineno);
+		}
 		if (s->v.Return.value) {
 			VISIT(st, expr, s->v.Return.value);
 			st->st_cur->ste_returns_value = 1;
@@ -1278,6 +1289,12 @@
 			return 0;
 		break;
         case Yield_kind:
+		if (st->st_cur->ste_type != FunctionBlock) {
+			PyErr_SetString(PyExc_SyntaxError,
+				YIELD_OUTSIDE_FUNCTION);
+		        PyErr_SyntaxLocation(st->st_filename,
+			             e->lineno);
+		}
 		if (e->v.Yield.value)
 			VISIT(st, expr, e->v.Yield.value);
                 st->st_cur->ste_generator = 1;
Index: Lib/test/test_syntax.py
===================================================================
--- Lib/test/test_syntax.py	(revision 68142)
+++ Lib/test/test_syntax.py	(working copy)
@@ -528,6 +528,16 @@
     def test_break_outside_loop(self):
         self._check_error("break", "outside loop")
 
+    def test_yield_outside_function(self):
+        # Issue XXXX: raise a SyntaxError even if the compiler
+        # trims the code because of a "if 0"
+        self._check_error("if 0: yield",               "outside function")
+        self._check_error("class C:\n    if 0: yield", "outside function")
+
+    def test_return_outside_function(self):
+        self._check_error("if 0: return",               "outside function")
+        self._check_error("class C:\n    if 0: return", "outside function")
+
     def test_delete_deref(self):
         source = re.sub('(?m)^ *:', '', """\
             :def foo(x):