Is a static constructor to configure spdlog safe to use?

[CPickens42]

Hello,

I'm using spdlog and I have this in my code (C++20):

#include <spdlog/spdlog.h>
#include <spdlog/sinks/stdout_color_sinks.h>


[[maybe_unused]] auto static_ctor = std::invoke([]() {  /* NOLINT */
    // see https://spdlog.docsforge.com/v1.x/0.faq/#switch-the-default-logger-to-stderr
    spdlog::set_default_logger(spdlog::stderr_color_mt("some_arbitrary_name"));
    spdlog::set_default_logger(spdlog::stderr_color_mt(""));
    spdlog::set_pattern("%^[%Y-%m-%d %T.%F | %-8l]%$ %v");
    return nullptr;
});

I'm unsure of the safety of this. Could I encounter a "static initialization fiasco"? If so, in which cases?
So far I don't see the issue since, for what I saw, there is no static initialization in spdlog, but I would like to know a bit better.

This is done like this to avoid to repeat the configuration of spdlog in every tests, in every main and so on.

[Iravoo]

I'm interested in this as well. Maybe @tt4g has an idea? 🙂

[tt4g]

In my personal opinion, I do not use static variables to avoid "Don't repeat yourself".
It may crash depending on the initialization order of static variables as described in static initialization fiasco And the initialization order of static variables is difficult for developers to control.
It is a real shame to struggle with static variables introduced for the sake of ease.

Note that static variables can cause problems depending on the order in which the destructors are called.

See also:

• logger object is not ensured to outlive all static local variables that it uses #2113
• [Question] Is it safe to call loggers factories during static initialization? #2298

I would define the functions that configure spdlog.
Calling the functions that configure spdlog repeatedly in main() is tedious, but the tedious work is better than the risk of encountering bugs that cannot be avoided.

[CPickens42]

Thank you @tt4g, your answer was really clear. 🙂 !