https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66941
Bug ID: 66941
Summary: Missing diagnostic "extraneous template parameter list
in template specialization"
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: miyuki at gcc dot gnu.org
Target Milestone: ---
Consider this testcase:
$cat genpreds1_min.cc
template <typename>
class A;
template <int>
struct B;
template <typename>
struct C;
template <>
template <int N>
struct C <B <N> >
{
template<typename T>
A <B <N> >
m_fn(T);
};
template <int N>
template <typename T>
A <B <N> >
C <B <N> >::m_fn (T)
{
}
EDG rejects it with the following error:
/opt/intel/bin/icpc -c genpreds1_min.cc
genpreds1_min.cc(22): error: incomplete type is not allowed
C <B <N> >::m_fn (T)
^
genpreds1_min.cc(22): error: template argument list must match the parameter
list
C <B <N> >::m_fn (T)
^
compilation aborted for genpreds1_min.cc (code 2)
Clang gives warning:
/opt/clang-trunk/bin/clang++ -c genpreds1_min.cc
genpreds1_min.cc:10:1: warning: extraneous template parameter list in template
specialization
template <>
^~~~~~~~~~~
1 warning generated.
But GCC silently accepts this code. I suppose that GCC could warn about:
template <typename>
struct base {};
template <typename>
struct s {};
template <>
template <typename T>
struct base <s <T> > {};
like Clang does (note: in this case EDG accepts the code without
warnings/errors).
