https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65943
Bug ID: 65943
Summary: template keyword required for base-specifier that
names member of the current instantiation
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
Target Milestone: ---
template<class A> struct X
{
template<class B> struct Base;
template<class B> struct Data;
};
template<class A>
template<class B>
struct X<A>::Data : X<A>::Base<B>
{ };
This fails to compile:
f.cc:9:33: error: ‘typename X<A>::Base’ names ‘template<class A> template<class
B> struct X<A>::Base’, which is not a type
struct X<A>::Data : X<A>::Base<B>
^
f.cc:9:27: error: ‘typename X<A>::Base’ names ‘template<class A> template<class
B> struct X<A>::Base’, which is not a type
struct X<A>::Data : X<A>::Base<B>
^
f.cc:10:1: error: expected class-name before ‘{’ token
{ };
^
Clang and EDG accept it.
It compiles if the base-specifier is changed to X<A>::template Base<B>, but I
think the addition of "but the name is not a member of the current
instantiation" to C++11 14.2 [temp.names] p4 should make it valid.
In any case, http://open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1710 will
definitely make it valid. See also
http://open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1812 and
http://open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#314
