c++/10627: [diagnostic] improve error message when a template is used without argument list

[giovannibajo@libero.it]

>Number:         10627
>Category:       c++
>Synopsis:       [diagnostic] improve error message when a template is used without argument list
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Mon May 05 11:56:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Giovanni Bajo
>Release:        3.4 CVS 20030503
>Organization:
>Environment:
i686-pc-cygwin
>Description:
Compiling this on mainline (3.4):
-----------------------------------------------
template <class> struct A {};

A a;
-----------------------------------------------
gccbug2.cpp:3: error: `A' does not name a type

This is a progression compared to previous versions (which
were giving a mere syntax error), but I think it could
be improved a little bit. Comeau/EDG gives:

"gccbug2.cpp", line 3: error: argument list for class template "A" is missing
  A a;
  ^

which is easier for the user.
>How-To-Repeat:
Compile the above snippet.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: