[Bug c++/32565] New: [4.3 regression] ICE with specialization of variadic template

["reichelt at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

The following valid code snippet triggers an ICE on mainline:

============================================================
template<typename...> struct A;

template<template<int...> class T> struct A<T<0> > {};

template<int> struct B;

A<B<0> > a;
============================================================

bug.cc:7: internal compiler error: tree check: expected class 'expression',
have 'constant' (integer_cst) in unify, at cp/pt.c:12796
Please submit a full bug report, [etc.]


A similar testcase generates a slightly different error message:

============================================================
template<typename...> struct A;

template<template<typename...> class T> struct A<T<int> > {};

template<typename> struct B;

A<B<int> > a;
============================================================

bug.cc:7: internal compiler error: tree check: expected class 'expression',
have 'type' (integer_type) in unify, at cp/pt.c:12796
Please submit a full bug report, [etc.]


-- 
           Summary: [4.3 regression] ICE with specialization of variadic
                    template
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, monitored
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32565