https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68411
Bug ID: 68411
Summary: Error in template instantion, cause recursive template
reference.
Product: gcc
Version: 5.2.0
Status: UNCONFIRMED
Severity: critical
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: msnkipa at mail dot ru
Target Milestone: ---
This code could not be compiled:
std::exception_ptr safe(std::function<void()>); // Defined somewhere in file
template<typename F, typename... Args>
auto safe(typename
std::enable_if<std::is_void<std::result_of<F(Args...)>>::value, int*>::type,
F func, Args... args) -> std::pair<decltype(func(args...)),
std::exception_ptr>
{
decltype(func(args...)) result{};
std::exception_ptr exp{ /*safe([&]{ result = func(args...); })*/ };
return { result, exp };
}
template<typename F, typename... Args, typename = int>
auto safe(typename
std::enable_if<!std::is_void<std::result_of<F(Args...)>>::value, int*>::type,
F func, Args... args) -> std::exception_ptr
{
return safe([&]{ func(args...); });
}
template<typename F, typename... Args>
auto safe(F func, Args... args) -> typename
std::conditional<std::is_void<decltype(func(args...))>::value,
std::exception_ptr, std::pair<decltype(func(args...)),
std::exception_ptr>>::type
{
return safe(nullptr, func, args...);
}
int main()
{
safe([&] { std::cout << "Hello" << std::end; });
}
Error is:
C:/mingw-w64/mingw64/x86_64-w64-mingw32/include/c++/type_traits: In
instantiation of 'struct std::is_reference<dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(!
std::is_void<std::result_of<_Functor(_ArgTypes ...)> >::value), int*>::type, F,
Args ...) [with F = dcs::safe(typename std::enable_if<(! ... many such lines
...
C:/mingw-w64/mingw64/x86_64-w64-mingw32/include/c++/type_traits:544:12: fatal
error: template instantiation depth exceeds maximum of 900 (use
-ftemplate-depth= to increase the maximum)
struct is_reference
PS: clang compile this code without problems.
