libclang has problems to process files with BOM:
- Create and open a file like foo.cpp below.
- A diagnostic fatal error: 'someNonExistingFile.h' file not found will be indicated, as expected.
- From the context menu of the editor, choose "Add UTF-8 BOM on Save", then insert a space and hit Ctrl+S to save with the BOM.
- Close and re-open the file. The diagnostic error: expected "FILENAME" or <FILENAME> (Lexical or Preprocessor Issue) will be indicated.
- Insert some space --> this diagnostic is gone and the correct one from Step 2 is displayed again.