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
MSVC cannot handle MinGW-esque /c/foo paths, convert them to C:/foo.
We cannot resolve other paths starting with / like /home/foo so leave
them as-is so the user gets an error/warning from the compiler/linker.
These paths are commonly found in pkg-config files generated using
Autotools inside MinGW/MSYS and MinGW/MSYS2 environments.
Currently this is only done for PkgConfigDependency.
Escaping spaces with '\ ' is the only way that works with both
pkg-config and pkgconf, so quote that way and unquote inside Meson.
This should work on all platforms.
Also fix the unit test to do the same.
https://github.com/pkgconf/pkgconf/issues/153