Re: [Patch] Add TYPE_NAME_IDENTIFIER

[Jason Merrill <jason at redhat dot com>]

On 04/13/2014 12:20 PM, Paolo Carlini wrote:
> this is a small clean-up discussed some time ago with Jason. The basic
> idea seems pretty straightforward to me. However, at variance with that
> discussion, I'm not proposing replacing the C++ front-end
> TYPE_IDENTIFIER with the new TYPE_NAME_IDENTIFIER because, as far as I
> can see, that front-end really needs DECL_NAME (TYPE_NAME
> unconditionally. Eg, code like (in error.c):
>
>      case TEMPLATE_TEMPLATE_PARM:
>        /* For parameters inside template signature.  */
>        if (TYPE_IDENTIFIER (t))
>      pp_cxx_tree_identifier (pp, TYPE_IDENTIFIER (t));
>        else
>      pp_cxx_canonical_template_parameter (pp, t);
>        break;
>
> assumes that TYPE_IDENTIFIER is indeed an identifier and that would not
> be necessarily the case in C++ when TYPE_NAME_IDENTIFIER boils down to
> TYPE_NAME itself (in practice, fails like eg, abi/mangle12.C, where
> TYPE_NAME is a TEMPLATE_DECL).

You could avoid that issue if TYPE_NAME_IDENTIFIER checked for 
IDENTIFIER_NODE rather than TYPE_DECL.

Jason