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

[Pedro Alves <palves@redhat.com>]

On 07/24/2014 11:35 PM, Cary Coutant wrote:
>> 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?
> 
> I think conversion ops really are a special case. 

Thanks Cary.  FWIW, I agree.

(GDB 7.8 hasn't been released yet, though it's close.  If this
patch is approved as is, we'll be able to have the crash
fixed there.  If this requires a significant rewrite though,
I'm afraid I might not be able to do it myself anytime soon.)

> It's the only case
> where the template parameters refer to the template argument list from
> the cast operator's enclosing template. In a cast expression, like
> anywhere else you might have a template parameter, the template
> parameter refers to the template argument list of the immediately
> enclosing template.
> 
> I think this note from Section 5.1.3 (Operator Encodings) of the ABI
> is what makes this a special case (it's an informative comment in the
> document, but seems to me to be normative):
> 
> "For a user-defined conversion operator the result type (i.e., the
> type to which the operator converts) is part of the mangled name of
> the function. If the conversion operator is a member template, the
> result type will appear before the template parameters. There may be
> forward references in the result type to the template parameters."
> 

-- 
Thanks,
Pedro Alves