Allow methods on the compiler object to receive internal dependencies,
as long as they only specify compiler/linker arguments or other
dependencies that satisfy the same requirements.
This is useful if you're using internal dependencies to add special
"-D" flags such as -DNCURSES_WIDECHAR, -D_XOPEN_SOURCE_EXTENDED or
-DGLIB_STATIC_COMPILATION.
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