[llvm] Remove dependence on <ciso646> (PR #73273)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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git-clang-format --diff 28d91a6e17c58c129eda75c53448c8a81d63b445 d2b2d842b5b1a2e70d8e33ea52a0ab3bc55f1606 -- llvm/include/llvm/Support/Threading.h llvm/lib/DebugInfo/GSYM/LookupResult.cpp
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View the diff from clang-format here.
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``````````diff
diff --git a/llvm/include/llvm/Support/Threading.h b/llvm/include/llvm/Support/Threading.h
index e83cb67ac1..13d21b0f3e 100644
--- a/llvm/include/llvm/Support/Threading.h
+++ b/llvm/include/llvm/Support/Threading.h
@@ -18,8 +18,8 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Config/llvm-config.h" // for LLVM_ON_UNIX
 #include "llvm/Support/Compiler.h"
-#include <version>
 #include <optional>
+#include <version>
 
 #if defined(_MSC_VER)
 // MSVC's call_once implementation worked since VS 2015, which is the minimum

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https://github.com/llvm/llvm-project/pull/73273