diff --git a/pycparserext/ext_c_parser.py b/pycparserext/ext_c_parser.py
index 5308ea6..db59694 100644
--- a/pycparserext/ext_c_parser.py
+++ b/pycparserext/ext_c_parser.py
@@ -546,6 +546,14 @@ def p_statement(self, p):
         """
         p[0] = p[1]
 
+    def p_gnu_primary_expression_7(self, p):
+        """ primary_expression : __EXTENSION__ primary_expression """
+        p[0] = p[2]
+
+    def p_gnu_assignment_expression_2(self, p):
+        """ assignment_expression : __EXTENSION__ assignment_expression """
+        p[0] = p[2]
+
     def p_attribute_const(self, p):
         """ attribute : __CONST
         """
diff --git a/test/test_pycparserext.py b/test/test_pycparserext.py
index 183769f..f349cf3 100644
--- a/test/test_pycparserext.py
+++ b/test/test_pycparserext.py
@@ -348,6 +348,19 @@ def test_lvalue_gnu_statement_expression():
     print(GnuCGenerator().visit(ast))
 
 
+def test_gnu_extension_expression():
+    src = """
+      int func(int a) {
+        int i = (4,__extension__ 2);
+        char * name = __extension__ __PRETTY_FUNCTION__;
+        i = __extension__ i++;
+        i = __extension__((__extension__ i)++ + (--(__extension__ i)));
+        return __extension__(int)__extension__({; ; i;});
+     }
+    """
+    assert _round_trip_matches(src)
+
+
 def test_empty_struct_declaration():
     src = """
         typedef struct Foo {