https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71095
Bug ID: 71095
Summary: Problem with captureless generic lambda and calling
function object with arguments passed by reference
Product: gcc
Version: 6.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: karol.wozniak at email dot com
Target Milestone: ---
#include <utility>
struct do_some_stuff_by_ref {
template <typename... T> int operator()(T &...) const { return 42; };
};
int main() {
{ // compiles both
// g++-5 prog.cc -std=c++14
// g++-6 prog.cc -std=c++14
do_some_stuff_by_ref callable{};
int a = 0;
[callable](auto &&... x) {
return callable(std::forward<decltype(x)>(x)...);
}(a);
}
{ // compiles both
// g++-5 prog.cc -std=c++14
// g++-6 prog.cc -std=c++14
do_some_stuff_by_ref ignore_me{};
int a = 0;
[ignore_me](auto &&... x) {
(void)ignore_me;
do_some_stuff_by_ref callable{};
return callable(std::forward<decltype(x)>(x)...);
}(a);
}
{ // compiles
// g++-5 prog.cc -std=c++14
// fails to compile
// g++-6 prog.cc -std=c++14
// prog.cc:40:22: error: no match for call to ‘(do_some_stuff_by_ref)
(int)’
// return callable(std::forward<decltype(x)>(x)...);
// ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
int a = 0;
[](auto &&... x) {
do_some_stuff_by_ref callable{};
return callable(std::forward<decltype(x)>(x)...);
}(a);
}
return 0;
}
// $ g++-5 --version
// g++-5 (Debian 5.3.1-17) 5.3.1 20160429
//
// $ g++-6 --version
// g++-6 (Debian 6.1.1-1) 6.1.1 20160430
