[clang] [clang] Fix name conflict with `sys/mac.h` on AIX (PR #88644)

[Joseph Huber via cfe-commits]

================
@@ -50,6 +50,10 @@ const char *CudaVersionToString(CudaVersion V);
 // Input is "Major.Minor"
 CudaVersion CudaStringToVersion(const llvm::Twine &S);
 
+// We have a name conflict with sys/mac.h on AIX
+#ifdef SM_32
+#undef SM_32
+#endif
----------------
jhuber6 wrote:

We already do that, the problem is that `CudaArch::SM_32` will still invoke the preprocessorr, see https://godbolt.org/z/84xKej5K9. We can't do this from a header level, we'd need to do it around every single use as far as I know, which might be doable?

https://github.com/llvm/llvm-project/pull/88644