be portable to miscellaneous CPU architectures #666
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This option is universally available, and the Quake III engine assumes it. It is the default on x86 but not on, for instance, ARM and PowerPC.
cmake already has a standard way to distinguish between 32- and 64-bit platforms; there's no advantage in adding another.
There are more architectures than just x86, x86-64 and ARM, and the Quake III engine supports most of them. I haven't seen anything in OpenJK that is particularly platform-specific, other than what's fixed in this branch.
There are plenty of CPU architectures that are neither ARM nor the x86 family, for instance PowerPC and ARM64.
The mp3code came from Zinf (formerly FreeAmp) in which a similar endianness bug was fixed back in 2003 <https://bugs.debian.org/56472>. The bug is that the code uses LITTLE_ENDIAN as though it was a feature-test macro like Q3_LITTLE_ENDIAN, but actually it's always defined, regardless of platform: the actual test for endianness with <endian.h> is BYTE_ORDER == LITTLE_ENDIAN. As a result, it always takes the LE code path. Rather than trying to use <endian.h> in a portable way, I've just used the Quake 3 engine's equivalent macros. I'm surprised this wasn't fixed in JK2/JA already, since at least JK2 ran on Mac back when that meant PowerPC, but perhaps changes from the Mac port didn't all make it into Raven's GPL release.
xycaleth
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be portable to miscellaneous CPU architectures
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The Quake 3 engine is portable to various CPUs, and I haven't noticed anything JK-specific in OpenJK that wouldn't be, other than an endianness fix in the MP3 code which is fixed in this branch. The current CMake files assume that everything non-ARM is x86, but the current "ARM" code-path is equally valid for any non-x86 architecture; this branch adapts it accordingly.
The major potential portability issues are: