[libc] [llvm] [libc] Move libc_errno.h to libc/src/__support and make LIBC_ERRNO_MODE_SYSTEM to be header-only. (PR #143187)

[Alexey Samsonov via llvm-commits]

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@@ -9,6 +9,7 @@
 #ifndef LLVM_LIBC_SHARED_FP_BITS_H
 #define LLVM_LIBC_SHARED_FP_BITS_H
 
+#include "libc_common.h"
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vonosmas wrote:

Looks like you're adding this include only in shared headers that further include llvm-libc headers (but not all headers under `libc/shared/`. This feels a bit brittle, any idea how to ensure that this inclusion would happen? (if we actually need this "common" header at all - see below.

https://github.com/llvm/llvm-project/pull/143187