[clang] [llvm] [clang][Modules] Fixing Build Breaks When -DLLVM_ENABLE_MODULES=ON (PR #119473)

[Michael Spencer via llvm-commits]

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@@ -14,8 +14,6 @@
 #ifndef CLANG_SUPPORT_COMPILER_H
 #define CLANG_SUPPORT_COMPILER_H
 
-#include "llvm/Support/Compiler.h"
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Bigcheese wrote:

The include of this file needs to move to Attr.h, module imports can't be in a namespace, so putting the include in Attrs.inc is wrong.

You should also add a new top level module for the Support directory.

`module Clang_Support { requires cplusplus umbrella "clang/Support" module * { export * } }`

https://github.com/llvm/llvm-project/pull/119473