MSVC 145 (VS2026) fails to compile with internal compiler error.

[Agrael1]

Hello, thank you for the library!

I have an issue building under new Visual Studio 2026. It results in internal compiler error.
The problem is caused by constexpr variables inside function that are not static.

e.g.:

[[nodiscard]] constexpr auto type_name() noexcept -> std::string_view
{
    constexpr std::string_view function_name = std::source_location::current().function_name();
    static_assert(std::size(function_name) > 0u); // not static, local lifetime

    return [&] {
        static constexpr const auto name = reflect::fixed_string<char, std::size(function_name)>{
            function_name
        };
        return std::string_view{ name };
    }();
}

If I require the variable to be static, then it compiles fine.

[[nodiscard]] constexpr auto type_name() noexcept -> std::string_view
{
    constexpr static std::string_view function_name = std::source_location::current().function_name();
    static_assert(std::size(function_name) > 0u); // static, global lifetime

    return [&] {
        static constexpr const auto name = reflect::fixed_string<char, std::size(function_name)>{
            function_name
        };
        return std::string_view{ name };
    }();
}

[Please-just-dont]

Same here. This problem has been here for a while I think. I made an issue about it here and I made a reproducible example here, thought literally all it does is paste reflect header in an empty project, and the compiler refuses to compile with:

C1001 Internal compiler error.
Pointing to line 702 in reflect.h:
[[nodiscard]] constexpr auto type_name() noexcept -> std::string_view

I also compiled with Visual Studio 2026, the version is listed in the example.