https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105795
Bug ID: 105795
Summary: Miscompilation with [[no_unique_address]]
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: git at foonathan dot net
Target Milestone: ---
The following code should return 1:
```
struct empty
{};
template <typename T>
struct tuple_holder
{
[[no_unique_address]] T value;
};
struct tuple : tuple_holder<int>, tuple_holder<empty>
{};
constexpr auto make_tuple(int&& i, empty&& e)
{
return tuple{i, e};
}
int main()
{
auto tuple = make_tuple(1, empty{});
return static_cast<const tuple_holder<int>&>(tuple).value;
}
```
This is also the case with clang and GCC 11.1. However, starting with GCC 11.2,
the code returns 0 instead: https://godbolt.org/z/Gb6Kffnnc
