ERR_FAIL_COND_MSG sometimes doesn't print message

[KoBeWi]

Godot version:
fb12f54

Issue description:
So, uh, this happened

I'm not sure if it's possible to reliably reproduce it with minimal project.

[KoBeWi]

Okay, it's possible:
ReproductionProject.zip

Just run the project and spam Space. Sometimes there's wrong message.

[qarmin]

I see these messages all the time.

[profan]

Also seems to have been noted in #32143 (that it sometimes does one, and sometimes the other), this might be in part because the current implementation:

godot/core/error_macros.h

Lines 276 to 284 in f1146c2

	#define ERR_FAIL_COND_MSG(m_cond, m_msg) \
	{ \
	if (unlikely(m_cond)) { \
	ERR_EXPLAIN(m_msg); \
	_err_print_error(FUNCTION_STR, __FILE__, __LINE__, "Condition ' " _STR(m_cond) " ' is true."); \
	return; \
	} \
	_err_error_exists = false; \
	}

... of the various _MSG macros might be kind of silly, I can go back and make them not use ERR_EXPLAIN as an in-between and directly set the error string instead of using _err_set_last_error indirectly through ERR_EXPLAIN.

(at the time I figured getting this change through at all so people would start employing it everywhere in godot mattered most, but I can refine it now to not do unnecessary work)

but also if this implementation doesn't work, it must mean that ERR_EXPLAIN + the normal error macros before also didn't work sometimes, as it's essentially the exact same concept here, only condensed into a single macro.

[Xrayez]

Might be related: #31832 (comment).

[profan]

Also is anyone aware of how long ago the C Error: etc, C Function: etc part was stripped from godot? (or is it still there somewhere..?)
(from a build where it's still around, admittedly almost a year old)

If we don't care about that part fixing this current problem isn't hard, but it seems like a weird thing to have removed when having both the error cond and the message itself is quite useful in the debugger?

Found the commit: #21884

I guess I'll PR the simple fix for now and we can consider if maybe adding back the condition and function metadata is useful :)

edit: (scratch all this, need to debug the error message stuff I guess 🤔, new PR later)