D lang compilers have an option -release (or similar) which turns off
asserts, contracts, and other runtime type checking. This patch wires
that up to the b_ndebug flag.
Fixes#7082
Fortran: check for undeclared variables by forcing implicit none everywhere
C/C++: check for unused parameters and return types
removed unused variables from test cases
ci: do missing return and unused arg check with Github Actions
Also add a test() that can be run on all platforms.
Currently unit tests are only run on Linux, so this was only testing the
Ninja backend. This change reveals that build-by-default was broken with
the Visual Studio backend.
Jussi Pakkanen
Dylan Baker
Michael Hirsch, Ph.D
Nirbheek Chauhan