Re: AC_CXX_TEMPLATE_KEYWORD_QUALIFIER VS. GCC 3.4

[Bernardo Innocenti]

MAISONOBE Luc wrote:
> Bernardo Innocenti wrote:
>
> > the AC_CXX_TEMPLATE_KEYWORD_QUALIFIER test fails
> > with GCC 3.4.  I believe it's a bug in the test,
> > but I don't have access to the C++ standard to
> > verify.
>
> [...]
>
> I only have the 2 December 1996 draft handy yet, I am not sure the 
> standard says the same. Here is an extract of the relevant paragraph. 
> Could you check if it does work with gcc 3.4 ?

No, it doesn't.  I've now found the official version of the standard
and it seems there were some interesting changes:

> When the name of a member template specialization appears after . or -> 
> in a postfix-expression, or after :: in a qualified-id that explicitely 
> depends on a template-argument (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* allox();
>      };
>      void f(X* p)
>      {
>              X* p1 = p->alloc<200>();
>                      // ill-formed: < means less than
>
>              X* p2 = p->template allox<200>();
>                      // fine: < starts explicit qualification
>      }
> --end example]

> From 14.2/4:

---cut---
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]

---cut---

So it seems GCC 3.4 is right and the test should be updated.

Shall I submit a patch?

--
 // Bernardo Innocenti - Develer S.r.l., R&D dept.
\X/  http://www.develer.com/