Fix Bison grammar issues preventing us from parsing CoreFoundation

regression/ansi-c/enum_with_underlying_type/test.c

@@ -0,0 +1,19 @@
+typedef unsigned short USHORT;
+
+enum A : USHORT
+{
+  AV
+};
+enum B : unsigned short
+{
+  BV
+};
+enum C : signed long long
+{
+  CV
+};
+
+int main(void)
+{
+  return 0;
+}

regression/ansi-c/enum_with_underlying_type/test.desc

@@ -0,0 +1,12 @@
+CORE
+test.c
+
+^EXIT=0$
+^SIGNAL=0$
+--
+^PARSING ERROR$
+--
+A previous attempt to allow underlying type specifications didn't allow typedef
+names or multi word types (e.g. unsigned int). We still don't actually fully
+apply the underlying type to the enum, but this at least lets us use parse code
+that uses this feature.

regression/ansi-c/function_with_postfix_attributes/test.c

@@ -0,0 +1,15 @@
+inline int inline_function_with_postfix_attributes(void)
+  __attribute__((not_a_real_attribute))
+{
+  return 0;
+}
+
+int non_inline_with_postfix_attributes(void)
+  __attribute__((not_a_real_attribute))
+{
+  return 0;
+}
+
+int main(void)
+{
+}

regression/ansi-c/function_with_postfix_attributes/test.desc

@@ -0,0 +1,11 @@
+CORE gcc-only
+test.c
+
+^EXIT=0$
+^SIGNAL=0$
+--
+^PARSING ERROR$
+--
+gcc doesn't support postfix attributes but clang does, and Apples CoreFoundation framework makes use of this for availability macros.
+
+Testing both the inline and non-inline variants because these are different cases in our parser.

src/ansi-c/parser.y

@@ -1837,13 +1837,21 @@ enum_name:
         }
         ;
 
+basic_type_name_list:
+    basic_type_name
+  | basic_type_name_list basic_type_name
+
+enum_underlying_type:
+    basic_type_name_list
+  | typedef_name
+
 enum_underlying_type_opt:
         /* empty */
         {
           init($$);
           parser_stack($$).make_nil();
         }
-        | ':' basic_type_name
+        | ':' enum_underlying_type
         {
           $$=$2;
         }
@@ -2995,14 +3003,14 @@ function_head:
           PARSER.add_declarator(parser_stack($$), parser_stack($1));
           create_function_scope($$);
         }
-        | declaration_specifier declarator
+        | declaration_specifier declarator post_declarator_attributes_opt
         {
           init($$, ID_declaration);
           parser_stack($$).type().swap(parser_stack($1));
           PARSER.add_declarator(parser_stack($$), parser_stack($2));
           create_function_scope($$);
         }
-        | type_specifier declarator
+        | type_specifier declarator post_declarator_attributes_opt
         {
           init($$, ID_declaration);
           parser_stack($$).type().swap(parser_stack($1));