[libc-commits] [libc] [libc][clang-tidy] Add llvm-header-guard to get consistant naming and prevent file copy/paste issues. (PR #66477)

[Guillaume Chatelet via libc-commits]

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@@ -6,6 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_CALLONCE_H
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gchatelet wrote:

This one was missing a header

https://github.com/llvm/llvm-project/pull/66477