On preprocessing targets changes behavior to emit/omit line directives like `#line` and `#<linenum>`.
(cherry picked from commit dcae35f1585ef419b12809658493d084e1692241)
Co-authored-by: Nikita Kniazev <nok.raven@gmail.com>
Various restructure of test framework handling of paths to avoid duplicate path editing which caused failed tests. Adjust many tests to deal with added subdirectories in build outputs now that toolset requirements are active.