[Bug c++/13520] New: gcc crashes with inheritance + default template parameter of nested template type

["hetadres at email dot com" <gcc-bugzilla at gcc dot gnu dot org>]

g++ crashes when instanciating template class Host in the following code.
----------
template<typename regular_type> class Policy {};


template <
	typename regular_type,
	template<typename> class OriginalPolicy
	>
class ChangedPolicy_impl {};

  
template <template<typename> class OriginalPolicy > class ChangedPolicy {
public:
	template<typename regular_type> class Type : public 
ChangedPolicy_impl<regular_type,OriginalPolicy> { };
};


template <
	typename regular_type,
	template<typename> class Policy1,
	template<typename> class Policy2 = ChangedPolicy<Policy1>::Type
	> class Host : public Policy1<regular_type>, 
		       public Policy2<regular_type> { };


int main() {
	Host<void, Policy>h;
	return 0;
}
----------
$ gcc -c try.cxx
try.cxx: In instantiation of `Host<void, Policy, ChangedPolicy<OriginalPolicy>::
Type>':
try.cxx:26:   instantiated from here
try.cxx:22: internal error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://bugs.gentoo.org/> for instructions.


I'm not absolutely sure about line 20 ("template<typename> class Policy2 = 
ChangedPolicy<Policy1>::Type"), maybe it should be "template<typename> class 
Policy2 = typename ChangedPolicy<Policy1>::Type". But then gcc says:
try.cxx:21: `template<template<class> class OriginalPolicy> template<class
   regular_type> class ChangedPolicy<OriginalPolicy>::Type' used without
   template parameters
try.cxx:21: ISO C++ forbids declaration of `type name' with no type
try.cxx:21: invalid default template argument
try.cxx: In function `int main()':
try.cxx:26: template argument 3 is invalid
try.cxx:26: ISO C++ forbids declaration of `h' with no type


I need this code to be working, because i have to hand it in at the University 
of Antwerp next month :-/

Thanks for your help.

-- 
           Summary: gcc crashes with inheritance + default template
                    parameter of nested template type
           Product: gcc
           Version: 3.2.3
            Status: UNCONFIRMED
          Severity: critical
          Priority: P1
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hetadres at email dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13520