This is not working because spawning cargo for each tests is too slow,
and cannot even re-use the same target directory because it would block
on the cargo lock file. and rebuild all the dependences because of
different flags
Collect all tests are build time in build.rs and generate Rust code that
uses #[test] annotated functions. This gives nice reporting and the
ability to run individual tests.
* Fix text-file-busy error when running the binary by replacing the use
of named temp file with simply using the input source file and the
extension replaced. A scope guard make sure to also delete the binary.
* Fix hard-coded library dependencies by sharing code with the cmake
xtask that needs the same list.
This extracts a compiler command line from the cc crate, runs the
compiler and tries to run the resulting binary. Unfortunately the latter
fails still.
