[libcxx-commits] [libcxx] [libcxx] Cache file attributes during directory iteration. (PR #93316)

[Louis Dionne via libcxx-commits]

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@@ -353,6 +353,12 @@
 #define _LIBCPP_AVAILABILITY_HAS_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19
 #define _LIBCPP_AVAILABILITY_BAD_EXPECTED_ACCESS_KEY_FUNCTION _LIBCPP_INTRODUCED_IN_LLVM_19_ATTRIBUTE
 
+// This controls the availability of populating cache for directory entry
+// filesystem system. A directory_iterator builds cache for directory_entry
+// in the library.
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ldionne wrote:

```suggestion
// This determines whether std::filesystem::directory_entry caches all the properties
// it contains, which improves the performance when accessing a directory entry.
// Code in the headers like filesystem::directory_entry's implementation needs to
// know whether the dylib populated the cache or not.
```

https://github.com/llvm/llvm-project/pull/93316