From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 15/17] scope: give a scope for labels & gotos
Date: Tue, 14 Apr 2020 17:59:18 -0700
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To: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
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On Tue, Apr 14, 2020 at 4:09 PM Luc Van Oostenryck
<luc.vanoostenryck@gmail.com> wrote:
>
> +                       if (s->scope != s->declared_scope) {
>
> This comparison can never succeed for labels declared with __label__
> because s->scope is a block scope and s->declared_scope a label one.

Hold on.. I'm sure I tested it.

Oh.

What I tested wasn't what I sent you, and I'd fixed things due to the
testing but not updated the patch file.

Oops.

The test is supposed to be

                        if (s->declared_scope != label_scope) {

which is the whole point of that 'declared_scope'.

So the concept of the patch is that the 'declared_scope' (and
'label_scope') are the same kind of scope (and comparable): it is the
applicability of the label itself (either the whole function or some
sub-expression statement).

And the the visibility of the -symbol- ends up being different, and is
the s->scope thing.

But while my testing wasn't quite as limited as my wrong-version patch
implied, it _was_ limited. So it might miss some other case.

              Linus