https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101960
Bug ID: 101960
Summary: std::tuple with an array element is rejected as a
named return type
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: wjwray at gmail dot com
Target Milestone: ---
This fails to compile, going back many revisions, in any std version:
https://godbolt.org/z/Kz9Mnz9aW
#include <tuple>
std::tuple<int[1]> f() {
std::tuple<int[1]> t;
return t;
}
GCC rejects with: ​error: array used as initializer
Clang rejects with: error: array initializer must be an initializer list
(The Compiler Explorer link shows it working in Clang+libc++ and MSVC.)
However, this works:
std::tuple<int[1]> g() { return {}; }
and so does this (workaround: return by-reference, then copy):
constexpr std::tuple<int[1]>& h(std::tuple<int[1]>&& t = {}) {
return t;
}
constexpr auto t = h();
(The only way I find with libstdc++ to make a constexpr tuple<T[N]>)
