[clang] [llvm] [AArch64] Decouple feature dependency expansion. (PR #94279)

[Alexandros Lamprineas via cfe-commits]

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@@ -27,7 +27,7 @@ int main(void) {
   (void)__builtin_cpu_supports("x86-64-v4");
   (void)__builtin_cpu_supports("x86-64-v5"); // expected-warning {{invalid cpu feature string for builtin}}
 #else
-  if (__builtin_cpu_supports("neon")) // expected-warning {{invalid cpu feature string for builtin}}
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labrinea wrote:

If we want the target attribute to accept it then we should accept it here too, otherwise be consistent and reject in both cases.

https://github.com/llvm/llvm-project/pull/94279