[clang] [llvm] [llvm][clang] Sandbox filesystem reads (PR #165350)

[Ben Langmuir via cfe-commits]

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@@ -1447,6 +1448,8 @@ class directory_iterator {
   explicit directory_iterator(const Twine &path, std::error_code &ec,
                               bool follow_symlinks = true)
       : FollowSymlinks(follow_symlinks) {
+    sandbox::violationIfEnabled();
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benlangmuir wrote:

Why are these violations caught here in the wrapper API instead of the underlying `directory_iterator_construct`, `directory_iterator_increment`, etc?

https://github.com/llvm/llvm-project/pull/165350