As a side-effect from #8885 `find_program()` returns now `Executable`
objects when `meson.override_find_program` is called with an
executable target. To resolve this conflict the missing methods
from `ExternalProgram` are added to `BuildTarget`.
We don't need the legacy variable name system as for dependency()
fallbacks because meson.override_find_program() is largely used already,
so we can just rely on it.
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
Otherwise we can't do the following workflow:
if not find_program('foo', required : false).found()
subproject('provides-foo')
endif
Where 'provides-foo' has a meson.override_find_program() on
a configure_file() or similar.
Daniel Mensinger
Jussi Pakkanen
Xavier Claessens
Dylan Baker
Nirbheek Chauhan