Reporitng libstdc++ bug without account to Bugzilla

Reporitng libstdc++ bug without account to Bugzilla

[Palmu, Miro M]

Hi

I think I found libstdc++ bug and I tried to report to Bugzilla but "user account creation has been restricted".

So I'm going to report it here in hope that someone with a account could report it to Bugzilla if they seem it fit.

Using gcc 13.2 with -std=c++23 code below (https://godbolt.org/z/Kc36rcMYx) does not compile even if all compile time
allocations are freed before returning from compile time context. MSVC is able to compile it.

I was suggested elsewhere that it could be some oversight in the SSO implementation.
 
```
#include <string>
#include <functional>
#include <algorithm>
#include <vector>

using namespace std;
using namespace std::literals;

constexpr auto foo() {
    const auto vec = vector{ "a"s, "b"s, "c"s };
    return ranges::fold_left(vec, ""s, plus{});
}

constexpr auto bar() {
    return foo().size();
}

int main() {
    constexpr auto _ = bar(); // This does not compile
}
```

Error message:

```
<source>: In function 'int main()':
<source>:19:27:   in 'constexpr' expansion of 'bar()'
<source>:15:23:   in 'constexpr' expansion of 'foo()()'
<source>:19:28:   in 'constexpr' expansion of 'std::ranges::__fold_left_fn::operator()(_Range&&, _Tp, _Fp) const [with _Range = const std::vector<std::__cxx11::basic_string<char>, std::allocator<std::__cxx11::basic_string<char> > >&; _Tp = std::__cxx11::basic_string<char>; _Fp = std::plus<void>](vec, std::literals::string_literals::operator""s(const char*, std::size_t)(0), (std::plus<void>(), std::plus<void>()))'
<source>:19:28:   in 'constexpr' expansion of 'std::__cxx11::basic_string<char>((* & std::move<__cxx11::basic_string<char>&>(__init)))'
<source>:19:28: error: accessing 'std::__cxx11::basic_string<char>::<unnamed union>::_M_allocated_capacity' member instead of initialized 'std::__cxx11::basic_string<char>::<unnamed union>::_M_local_buf' member in constant expression
   19 |     constexpr auto _ = bar();
      |                            ^
```

Miro Palmu

Re: Reporitng libstdc++ bug without account to Bugzilla

[Jonathan Wakely]

On Mon, 20 Nov 2023 at 14:23, Palmu, Miro M wrote:
>
> Hi
>
> I think I found libstdc++ bug and I tried to report to Bugzilla but "user account creation has been restricted".
>
> So I'm going to report it here in hope that someone with a account could report it to Bugzilla if they seem it fit.

No, but if you email the account creation address as suggested by
bugzilla, then we can create an account for you.