[clang] [clang][DependencyScanning] Add a Clang Driver Option to Enable Dependency Scanning Logging (PR #211966)

[Qiongsi Wu via cfe-commits]

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@@ -41,20 +41,43 @@ static uint64_t getTimestampMillis() {
 #endif
 }
 
+#ifdef _WIN32
+// Write to files opened with OF_Append may not be guaranteed to be atomic
+// on Windows. Both openLogFile and writeLineToFD are noops on Windows.
+static int openLogFile(StringRef Path) {
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qiongsiwu wrote:

Thanks for clarifying. As of now, we do not have competing implementations anymore and the guards are localized. 

https://github.com/llvm/llvm-project/pull/211966