Correct, this is just hacks for stuff you didn't manage to match exactly. Either that or your build environment isn't the same. Sadly, there are things which aren't really possible to reproduce in a byte-identical manner, things like exact file layout or variable declaration order, compilation order and that kinda stuff. And they might cause small but equivalent changes like different inlining/optimisation decisions, so it's really tricky to get it byte-exact.

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mitxela 2 hours ago | parent [-]

Why wouldn't those be possible to reproduce?

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Pannoniae 2 hours ago | parent [-]

"assign all these pointers to the correct types, a wrong guess leads to different COMDAT folding"

"get the order of local variables in this function right, otherwise the register allocation doesn't match. Oh and there's 150 local variables just in this function, good luck trying them all"

"Find out the translation unit boundaries exactly (assume there's no pdb otherwise this is trivial) and after doing so, figure out the order they were compiled in, otherwise it won't match"

"brute force the compilation flags for the project and if you're done, also bruteforce it for the CRT or any other middleware which usually came prebuilt so it doesn't match the main game"

Should I continue;)

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mitxela an hour ago | parent [-]

Indeed it's a shitload of work. It's also possible and has been done. You don't have to only use global brute-force - you could also reverse engineer the compiler. The OOT/MM decomps achieved completeness without //COMPILERDIFF.

	▲	Pannoniae 35 minutes ago \| parent [-]
		Correct me if I'm wrong (I'm not very well-versed in game decomp scenes) but aren't all those bytematched decomps from 90s or at the latest early 2000s games? They didn't have global optimisation (MSVC introduced it in VS .NET or 2003 I think and many games didn't use it until later) So these are mostly problems with more advanced compilers yk