message: Don't print non-ASCII characters.
  We're already reporting where that is, but printing these
  might make the terminal unhappy.
  (also it is unclear what the format character is printing there,
  it seems to be different for gcc and clang, so I suspect it currently
  is actually picking up something else).
diff: @@ -245,7 +245,7 @@ bool ErrorDefinition::init() {
  rec(PP_CANNOT_READ_FILE_CONTENT, ERROR, PP,
  "Cannot read the file's content \"%s\". Only UTF-8 is supported");
  rec(PP_NON_ASCII_CONTENT, NOTE, PP,
  - "Non ASCII character detected, replaced by space \"%s\"");
  + "Non ASCII character detected, replaced by space");
  rec(PP_RECURSIVE_INCLUDE_DIRECTIVE, FATAL, PP,
  "Recursive include directive for file \"%s\"");
  rec(PP_ILLEGAL_TICK_LINE_VALUE, ERROR, PP,
  