Re: [C++ Patch] PR 51908

[Paolo Carlini <paolo dot carlini at oracle dot com>]

Hi,

On 06/05/2013 02:53 PM, Jason Merrill wrote:
> On 06/04/2013 08:34 PM, Paolo Carlini wrote:
> >         /* After seeing a decl-specifier-seq, if the next token is not a
> > -     "(", there is no possibility that the code is a valid
> > +     "(" nor '...', there is no possibility that the code is a valid
> >        expression.  Therefore, if parsing tentatively, we commit at
> >        this point.  */
> >
> > clearly in the case at issue of decl-specifier-seq followed by ellipsis
> > we may be parsing a perfectly valid declaration.
>
> Yes, but not an expression, which is why we are committing there: we 
> know it *has* to be a declaration.
I see, I didn't notice the reference to *expressions* in the comment.
>   The non-variadic case should hit that commit, so your change doesn't 
> seem to make the variadic case more consistent.
But the non-variadic case does *not* hit the commit, because is handled 
above:

  /* If the next token is a `)', `,', `=', `>', or `...', then there
     is no declarator. However, when variadic templates are enabled,
     there may be a declarator following `...'.  */
  if (token->type == CPP_CLOSE_PAREN
      || token->type == CPP_COMMA
      || token->type == CPP_EQ
      || token->type == CPP_GREATER)
    {
      declarator = NULL;
      if (parenthesized_p)
    *parenthesized_p = false;
    }

Thus it seems to me that the variadic case should also somehow not-hit 
the commit, do you agree?

Paolo.