Re: c++/9549: [3.4 regression] [New parser] ICE in regenerate_decl_from_template

[Martin Sebor <sebor at roguewave dot com>]

Wolfgang Bangerth wrote:
...
> I understand the reasoning for the necessity of the "template" keyword 
> here.
>
> This is 14.2.4 text and example from the 1997 draft I use:
>   When  the name of a member template specialization appears after .  or
>   -> in a postfix-expression, or after :: in a qualified-id that explic-
>   itly  depends on a template-argument (_temp.dep_), the member template
>   name must be prefixed by the keyword template.  Otherwise the name  is
>   assumed to name a non-template.  [Example:
>           class X {
>           public:
>                   template<size_t> X* alloc();
>           };
>           void f(X* p)
>           {
>                   X* p1 = p->alloc<200>();
>                           // ill-formed: < means less than
>
>                   X* p2 = p->template alloc<200>();
>                           // fine: < starts explicit qualification
>           }
>    --end example]
>
> Clearly, the lhs is not template-dependent. Has this been changed 
> afterwards? That might explain our mismatch!?
I believe so. Here's what's in the final text:

  -4-  When the name of a member template specialization
       appears after . or ­> in a postfix-expression, or after
       nested-name-specifier in a qualified-id, and the
       postfix-expression or qualified-id explicitly depends on
       a template-parameter (14.6.2), the member template name
       must be prefixed by the keyword template.
       Otherwise the name is assumed to name a non-template.
       [Example:

class X {
public:
    template<size_t> X* alloc();
    template<size_t> static X* adjust();
};

template<class T> void f(T* p)
{
    T* p1 = p->alloc<200>();
    // ill-formed: < means less than

    T* p2 = p->template alloc<200>();
    // OK: < starts template argument list

    T::adjust<100>();
    // ill-formed: < means less than

    T::template adjust<100>();
    // OK: < starts explicit qualification
}

--end example]


Martin