Re: problems with partial specialization of templates with template parameters

Re: problems with partial specialization of templates with template parameters

[Kriang Lerdsuwanakij]

On Wed, 18 Feb 1998, Andrey Slepuhin wrote:

> Hi,
> I have problems with partial specialization of templates
> with template parameters. I.e., trying to compile the following
> example:
> ----------------------------------------------
> template <class T, template <class T> class C>
> struct X
> {};
> 
> template <class T>
> struct Y
> {};
> 
> template <class T>
> struct Z
> {};
> 
> template <class T>
> struct X<T,Y>
> {};
> 
> void main()
> {
>   X<int,Y> a;
>   X<int,Z> b;
> }
> -----------------------------------------------
> I got with egcs-980205:
> -----------------------------------------------
> tmp1.cc:20: sorry, not implemented: use of `template_decl' in template type
> unification
> -----------------------------------------------
> Removing definition of X<T,Y> all works Ok. Also all works, if
> I remove "X<int,Z> b;" line (strange, isn't?). Is something
> really not implemented? Do I use invalid syntax? Or this is
> a bug? Any help is appreciated.
> 
> Regards,
> Andrey.
> 
> 

Thanks for the report.  It's a bug.  It tries to match X<int,Z> against
X<T,Y> and dies with the error message.  I'll post a patch for this.

--Kriang

problems with partial specialization of templates with template parameters

[Andrey Slepuhin]

Hi,
I have problems with partial specialization of templates
with template parameters. I.e., trying to compile the following
example:
----------------------------------------------
template <class T, template <class T> class C>
struct X
{};

template <class T>
struct Y
{};

template <class T>
struct Z
{};

template <class T>
struct X<T,Y>
{};

void main()
{
  X<int,Y> a;
  X<int,Z> b;
}
-----------------------------------------------
I got with egcs-980205:
-----------------------------------------------
tmp1.cc:20: sorry, not implemented: use of `template_decl' in template type
unification
-----------------------------------------------
Removing definition of X<T,Y> all works Ok. Also all works, if
I remove "X<int,Z> b;" line (strange, isn't?). Is something
really not implemented? Do I use invalid syntax? Or this is
a bug? Any help is appreciated.

Regards,
Andrey.

Patch for problems with partial specialization of templates with template parameters

[Kriang Lerdsuwanakij]

Hi

Here is the patch that fix the partial specialization bug reported
earlier.

Kriang

=======================================================

	* pt.c (unify): Handle TEMPLATE_DECL.


diff -rNpc gcc-old/cp/pt.c gcc/cp/pt.c
*** gcc-old/cp/pt.c	Wed Feb 18 16:24:52 1998
--- gcc/cp/pt.c	Wed Feb 18 16:24:03 1998
*************** unify (tparms, targs, ntparms, parm, arg
*** 5218,5223 ****
--- 5218,5227 ----
  	return 1;
        return 0;
  
+     case TEMPLATE_DECL:
+       /* Matched cases are handled by the ARG == PARM test above.  */
+       return 1;
+ 
      default:
        sorry ("use of `%s' in template type unification",
  	     tree_code_name [(int) TREE_CODE (parm)]);
diff -rNpc gcc-old/testsuite/g++.old-deja/g++.pt/ttp42.C
gcc/testsuite/g++.old-deja/g++.pt/ttp42.C
*** gcc-old/testsuite/g++.old-deja/g++.pt/ttp42.C	Wed Dec 31 16:00:00
1969
--- gcc/testsuite/g++.old-deja/g++.pt/ttp42.C	Wed Feb 18 16:26:33 1998
***************
*** 0 ****
--- 1,21 ----
+ template <class T, template <class T> class C>
+ struct X
+ {};
+ 
+ template <class T>
+ struct Y
+ {};
+ 
+ template <class T>
+ struct Z
+ {};
+ 
+ template <class T>
+ struct X<T,Y>
+ {};
+ 
+ int main()
+ {
+   X<int,Y> a;
+   X<int,Z> b;
+ }