[libc] [llvm] [libc]Add proxy header hdr/float-macros.h (PR #88674)

[via llvm-commits]

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@@ -9,163 +9,206 @@
 #ifndef LLVM_LIBC_MACROS_FLOAT_MACROS_H
 #define LLVM_LIBC_MACROS_FLOAT_MACROS_H
 
-// Suppress `#include_next is a language extension` warnings.
-#ifdef __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wgnu-include-next"
-#pragma clang diagnostic ignored "-Winclude-next-absolute-path"
-#else // gcc
-#pragma GCC system_header
-#endif //__clang__
-
-#include_next <float.h>
-
-#ifdef __clang__
-#pragma clang diagnostic pop
-#endif //__clang__
-
-#ifndef FLT_RADIX
+#ifdef __FLT_RADIX__
 #define FLT_RADIX __FLT_RADIX__
+#else 
+#define FLT_RADIX 2
 #endif // FLT_RADIX
 
-#ifndef FLT_EVAL_METHOD
+#ifdef FLT_EVAL_METHOD
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lntue wrote:

This should be `#ifdef __FLT_EVAL_METHOD__`.  Update similar checks in this file.

https://github.com/llvm/llvm-project/pull/88674