https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65415
Bug ID: 65415
Summary: using, base class static member function template, and
decltype
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: rs2740 at gmail dot com
>From http://stackoverflow.com/questions/29013260.
Minimized repro:
struct default_check
{
template<typename U> static int check(...);
};
struct is_addable : default_check
{
using default_check::check; // #1
using type = decltype(check<void>(0));
};
int main() {}
gcc HEAD 5.0.0 20150312 (experimental) reports
prog.cc:9:31: error: expected primary-expression before 'void'
using type = decltype(check<void>(0));
^
prog.cc:9:31: error: expected ')' before 'void'
prog.cc:9:16: error: expected type-specifier before 'decltype'
using type = decltype(check<void>(0));
^
i.e., for some reason the `check` brought in by `using` isn't found. Oddly
enough, commenting out line #1 makes the code compile.
(The original code in the linked SO question had a separate check() overload in
is_addable. In that case, lookup for some reason only found the is_addable
overload and not the base class one brought in by `using`)
