Re: [PATCH 2/3] PR other/61321 - demangler crash on casts in template parameters

[Jason Merrill <jason@redhat.com>]

On 05/27/2014 07:57 AM, Pedro Alves wrote:
> And after the fix for 59195, due to:
>
>   static void
>   d_print_cast (struct d_print_info *dpi, int options,
> 	       const struct demangle_component *dc)
>   {
>   ...
>     /* For a cast operator, we need the template parameters from
>        the enclosing template in scope for processing the type.  */
>     if (dpi->current_template != NULL)
>       {
>         dpt.next = dpi->templates;
>         dpi->templates = &dpt;
>         dpt.template_decl = dpi->current_template;
>       }
>
> when printing the template argument list of A (what should be "<sizeof
> (int)>"), the template parameter 0 (that is, "T_", the '**' above) now
> refers to the first parameter of the the template argument list of the
> 'A' template (the '*' above), exactly what we were already trying to
> print.  This leads to infinite recursion, and stack exaustion.  The
> template parameter 0 should actually refer to the first parameter of
> the 'function_temp' template.

It seems that the problem here is more general; a template argument list 
is not in scope within that same template argument list.  Can't we fix 
that without special-casing conversion ops?

Jason