[libc] [llvm] [libc] Add proxy header for fenv.h macro constants. #87863 (PR #87896)

[via llvm-commits]

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@@ -6,6 +6,7 @@
  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  */
 
+#include "mathlib.h"
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lntue wrote:

Revert the changes in this file.

https://github.com/llvm/llvm-project/pull/87896