[clang] [clang-tools-extra] [clang-tidy] Do not crash when an empty directory is used in the comp… (PR #156873)

[via cfe-commits]

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@@ -126,6 +126,10 @@ Improvements to clang-tidy
 - Improved :program:`clang-tidy` option `-quiet` by suppressing diagnostic
   count messages.
 
+- Improved :program:`clang-tidy` by not crashing when an empty 'directory'
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EugeneZelenko wrote:

```suggestion
- Improved :program:`clang-tidy` by not crashing when an empty `directory`
```

https://github.com/llvm/llvm-project/pull/156873