[PATCH] D65534: [clang] Change FileManager to use llvm::ErrorOr instead of null on failure

[Harlan Haskins via Phabricator via cfe-commits]

harlanhaskins marked 2 inline comments as done.
harlanhaskins added inline comments.


================
Comment at: clang/include/clang/Basic/FileManager.h:143
   ///
-  llvm::StringMap<DirectoryEntry*, llvm::BumpPtrAllocator> SeenDirEntries;
+  llvm::StringMap<llvm::ErrorOr<DirectoryEntry*>, llvm::BumpPtrAllocator>
+  SeenDirEntries;
----------------
jkorous wrote:
> Maybe we could replace this with some type that has hard-to-use-incorrectly interface instead of using `containsValue()`.
You're right, these should store `llvm::ErrorOr<DirectoryEntry &>` and use `std::err::no_such_file_or_directory` as a placeholder instead of `nullptr`.


================
Comment at: clang/include/clang/Basic/FileManager.h:217
   ///
-  /// This returns NULL if the file doesn't exist.
+  /// This returns a \c std::error_code if there was an error loading the file.
   ///
----------------
jkorous wrote:
> Does that mean that it's now safe to assume the value is `!= NULL` in the absence of errors?
That's the intent of these changes, yes, but it should also be documented. 👍


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D65534/new/

https://reviews.llvm.org/D65534