[clang] [ARM64EC] Fix compilation of intrin.h in ARM64EC mode. (PR #87717)

[Max Winkler via cfe-commits]

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@@ -44,7 +44,7 @@ unsigned char _InterlockedCompareExchange128_rel(__int64 volatile *_Destination,
                                                  __int64 *_ComparandResult);
 #endif
 
-#ifdef __x86_64__
+#ifdef __x86_64__ && !defined(__arm64ec__)
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MaxEW707 wrote:

@FreddyLeaf Curiosity how are you running clang. Since `intrin0.h` is treated as a system header warnings should be suppressed.

I couldn't repro the warning in my local testing due to `intrin0.h` being found via a system include path.

https://github.com/llvm/llvm-project/pull/87717