[clang] [clang][Dependency Scanning] Adding an API to Diagnose Invalid Negative Stat Cache Entries (PR #135703)

[Qiongsi Wu via cfe-commits]

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@@ -108,6 +108,32 @@ DependencyScanningFilesystemSharedCache::getShardForUID(
   return CacheShards[Hash % NumShards];
 }
 
+void DependencyScanningFilesystemSharedCache::diagnoseNegativeStatCachedPaths(
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qiongsiwu wrote:

Yes good catch! This should have a lock. 

https://github.com/llvm/llvm-project/pull/135703