[libc] [llvm] [libc] Add proxy headers for fenv types. (PR #88467)

[via llvm-commits]

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@@ -8,7 +8,7 @@
 
 #include "FPExceptMatcher.h"
 
-#include <fenv.h>
+#include "hdr/fenv_t.h"
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lntue wrote:

This file also call `fegetenv` and `fesetenv` from `fenv.h`.  Can you replace them with `fputil::get_env` and `fputil::set_env` respectively?  Also include `src/FPUtil/FEnvImpl.h` and update its dependency accordingly.

https://github.com/llvm/llvm-project/pull/88467