[clang] [clang] fix uefi target for aarch64 & x86_64 (PR #120632)

[Tristan Ross via cfe-commits]

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@@ -788,16 +789,28 @@ class LLVM_LIBRARY_VISIBILITY ZOSTargetInfo : public OSTargetInfo<Target> {
 // UEFI target
 template <typename Target>
 class LLVM_LIBRARY_VISIBILITY UEFITargetInfo : public OSTargetInfo<Target> {
+  llvm::Triple Triple;
+
 protected:
   void getOSDefines(const LangOptions &Opts, const llvm::Triple &Triple,
-                    MacroBuilder &Builder) const override {}
+                    MacroBuilder &Builder) const override {
+    DefineStd(Builder, "uefi", Opts);
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RossComputerGuy wrote:

We can probably get the cleanup PR first then this one. Kinda on the fence with the define one.

https://github.com/llvm/llvm-project/pull/120632