https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67426
Bug ID: 67426
Summary: Ambiguous overload between different function
templates, where one has non-deduced arg
Product: gcc
Version: 5.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: barry.revzin at gmail dot com
Target Milestone: ---
Consider this example (also in SO question
http://stackoverflow.com/q/32335523/2069064):
#include <utility>
template <int N>
using size_ = std::integral_constant<int, N>;
// (1)
template <int From>
void f(size_<From>, size_<From+1> )
{ }
// (2)
template <int From, int To>
void f(size_<From>, size_<To> )
{ }
int main()
{
f(size_<0>{}, size_<1>{});
}
gcc 5.2 declares this call ambiguous. Deduction from (1) to (2) succeeds
easily, should deduction from (2) to (1) not fail?
