Undefined behavior with no span on Windows

[DasLixou]

I'm on Windows and just did rustup +nightly component add miri.
When I do a new binary crate, run cargo add eframe --no-default-features and then put the following in main.rs:

use eframe;
fn main() {}

I get the following error with cargo +nightly miri run:

error: Undefined Behavior: calling a function with calling convention "Rust" using calling convention "C"
  |
  = note: Undefined Behavior occurred here
  = note: (no span available)
  = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior

[RalfJung]

This is probably an issue with "life before main" / a global constructor... we don't currently have way to show a useful backtrace when the stack is fully empty.

[RalfJung]

FWIW the error is in winit-0.30.12/src/platform_impl/windows/event_loop.rs:577:5 where an unsafe fn() is defined when it should be unsafe extern "C" fn().

EDIT: Filed as rust-windowing/winit#4435.