[libc-commits] [libc] [libc] Fix missing default value for errno config (PR #100175)

[via libc-commits]

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@@ -23,15 +25,17 @@
 // fullbuild mode, effectively the same as `LIBC_ERRNO_MODE_EXTERNAL`.
 #define LIBC_ERRNO_MODE_SYSTEM 5
 
-#ifndef LIBC_ERRNO_MODE
+#if !defined(LIBC_ERRNO_MODE) || LIBC_ERRNO_MODE == LIBC_ERRNO_MODE_DEFAULT
+#undef LIBC_ERRNO_MODE
 #if defined(LIBC_FULL_BUILD) || !defined(LIBC_COPT_PUBLIC_PACKAGING)
 #define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_THREAD_LOCAL
 #else
 #define LIBC_ERRNO_MODE LIBC_ERRNO_MODE_SYSTEM
 #endif
 #endif // LIBC_ERRNO_MODE
 
-#if LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_UNDEFINED &&                            \
+#if LIBC_ERRNO_MODE != LIBC_ERRNO_MODE_DEFAULT &&                              \
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lntue wrote:

add `LIBC_ERRNO_MODE_DEFAULT` to L44 below.

https://github.com/llvm/llvm-project/pull/100175