Re: [PATCH 1/3] struct_union_enum_specifier: set MOD_TOPLEVEL if toplevel(sym->scope)

[Oleg Nesterov <oleg@redhat.com>]

On 02/17, Luc Van Oostenryck wrote:
>
> On Fri, Feb 14, 2020 at 12:33:20PM +0100, Oleg Nesterov wrote:
> > With this change dissect can know the scope of SYM_STRUCT/UNION/ENUM,
> > see the next patch.
> >
> > Note that MOD_TOPLEVEL can be set even if struct/union/enum type is
> > private and bind_symbol() is not called.
>
> I don't like that very much. For example: why this is needed for
> struct/union/enum and not other types?

Do you mean builtin types like int_ctype? OK, I agree, this is slightly
inconsistent.

> Should it be possible to use the function toplevel() or add and
> helper for it in scope.c?

Well, toplevel() won't work if SYM_STRUCT/etc is anonymous, in this
case bind_symbol() is not called and thus sym->scope = NULL.

Consider

	struct { int m; } x;

	void func(void)
	{
		struct { int m; } x;

	}

we want to report the 2nd struct definition as "local"

   1:8                    def   s :x
   1:14                   def   m :x.m                             int
   1:19                   def   v x                                struct :x
   3:6                    def   f func                             void ( ... )
   5:16  func             def . s :x
   5:22  func             def . m :x.m                             int
   5:27  func             def . v x                                struct :x

so that this spam can be filtered out, but base->scope is NULL in both
cases.

> > IIUC nobody else looks at SYM_STRUCT->ctype.modifiers, "make check"
> > doesn't show any difference.
>
> Yes, it's true and it shouldn't make any difference but still I
> would prefer to not mix symbols and types more than they already are.

OK, will you agree with one-liner below? This should make toplevel() work.

Oleg.

--- a/parse.c
+++ b/parse.c
@@ -772,6 +772,7 @@ static struct token *struct_union_enum_specifier(enum type type,
 	}
 
 	sym = alloc_symbol(token->pos, type);
+	sym->scope = block_scope;
 	token = parse(token->next, sym);
 	ctx->ctype.base_type = sym;
 	token =  expect(token, '}', "at end of specifier");