[clang] [AArch64][PAC][clang][ELF] Support PAuth ABI compatibility tag (PR #85235)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,32 @@
+// Check that we can manually enable specific ptrauth features.
+
+// RUN: %clang -target aarch64 -c %s -### 2>&1 | FileCheck %s --check-prefix NONE
+// NONE: "-cc1"
+// NONE-NOT: "-fptrauth-intrinsics"
+// NONE-NOT: "-fptrauth-calls"
+// NONE-NOT: "-fptrauth-returns"
+// NONE-NOT: "-fptrauth-auth-traps"
+// NONE-NOT: "-fptrauth-vtable-pointer-address-discrimination"
+// NONE-NOT: "-fptrauth-vtable-pointer-type-discrimination"
+// NONE-NOT: "-fptrauth-init-fini"
+
+// RUN: %clang -target aarch64 -fptrauth-intrinsics -c %s -### 2>&1 | FileCheck %s --check-prefix INTRIN
+// INTRIN: "-cc1"{{.*}} {{.*}} "-fptrauth-intrinsics"
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MaskRay wrote:

`{{.*}} {{.*}} ` => ` {{.*}}`

https://github.com/llvm/llvm-project/pull/85235