[mono] Assume C99 support

[CoffeeFlux]

We don't seem to have been setting this define properly, but we can just remove the ifdef entirely

[ghost]

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Issue Details

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We don't seem to have been setting this define properly, but we can just remove the ifdef entirely

Author:	CoffeeFlux
Assignees:	-
Labels:	area-VM-meta-mono
Milestone:	-

[lambdageek]

We might be better off using the #else definitions of all that stuff. The C99 standard variadic macros are a mess https://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html that don't expand how you want anyway.

I think we could put a G_ATTR_FORMAT_PRINTF on g_log and get the benefit of warnings if the format string is incorrectly specified).

[vargaz]

Older msvc versions didn't have c99 support, newer ones might have it.

[tannergooding]

newer ones might have it.

AFAIK it still doesn't and things like _Complex and variable length arrays are still not supported.

[CoffeeFlux]

I believe they've committed to supporting all required C11 features, but that does mean some of the C99 stuff like VLAs isn't supported (since they were made optional).

Also seeing the build failures, I'm almost certainly just going to switch to the #else definitions here. I just haven't had a chance to update the PR.