[clang] [llvm] [PowerPC] Support -fpatchable-function-entry (PR #92997)

[Chen Zheng via cfe-commits]

================
@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -triple powerpc64-ibm-aix-xcoff -fsyntax-only -verify %s
+
+// expected-error at +1 {{'patchable_function_entry' attribute is not yet supported on AIX}}
+__attribute__((patchable_function_entry(0))) void f();
----------------
chenzheng1030 wrote:

I don't see a clean way to do that. The error message from in `clang/test/Sema/patchable-function-entry-attr.cpp` is to detect the missing targets in `clang/include/clang/Basic/Attr.td`. But this patch declares ppc/ppc64 as supported for Linux. So we have to emit the error message in some other place for example, in `clang/lib/Sema/SemaDeclAttr.cpp`.

https://github.com/llvm/llvm-project/pull/92997