This method simplifies the conversion of Feature objects to booleans.
Often, one has to use the "not" operator in order to treat "auto"
and "enabled" the same way.
"allowed()" also works well in conjunction with the require method that
is introduced in the next patch. For example,
if get_option('foo').require(host_machine.system() == 'windows').allowed() then
src += ['foo.c']
config.set10('HAVE_FOO', 1)
endif
can be used instead of
if host_machine.system() != 'windows'
if get_option('foo').enabled()
error('...')
endif
endif
if not get_option('foo').disabled() then
src += ['foo.c']
config.set10('HAVE_FOO', 1)
endif
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is problematic when we meson is installed in the different
root(say C:) while building from another root(say D:).
This is how it is done in mesonpep517 and causes problems
because of that.
Custom objects returned by modules must be subclass of ModuleObject and
have the state argument in its methods.
Add MutableModuleObject base class for objects that needs to be deep
copied on assignation.
The only advantage they have is they have the interpreter in arguments,
but it's already available as self.interpreter. We should discourage
usage of the interpreter API and rely on ModuleState object instead in
the future.
This also lift the restriction that a module method cannot add build
targets, but that was not enforced for snippet methods anyway (and some
modules were doing it) and it's really loose restriction as it should
check for many other things if we wanted to make it consistent.
We need to pass any generated sources down the CustomTarget
inititalizers so that they will generate a dependency correctly,
otherwise we get race conditions.
...Update 2, to be exact, since the Visual Studio linker only gained the
`/WHOLEARCHIVE:` feature since Visual Studio 2015 Update 2.
This checks whether we have the corresponding `cl.exe` which is
versioned at or after Visual Studio 2015 Update 2 before we try to apply
the `/WHOLEARCHIVE:xxx` linker flag. If we aren't, use built-in methods
in Meson to grab the object files of the dependent static lib's, along
with the objects that were `link_whole:`'ed into them, and feed this
list into the linker instead.
This would make `link_whole:` work on Visual Studio 2015 Update 1 and
earlier, including previous Visual Studio versions.