For some reason this was missing, but it should've always existed
since cc.find_library() returns an object that is internally an
ExternalDependency instance.
Currently meson only considers what compiler/linker were used by a
Target's immediate sources or objects, not the sources of libraries it's
linked with by the link_with and link_while keywords. This means that if
given 3 libraries: libA which is C++, libB which is C, and libC which is
also C, and libC links with libB which links with libA then linking libC
will be attempted with the C linker, and will fail.
This patch corrects that by adding the compilers used by sub libraries
to the collection of compilers considered by meson when picking a
linker.
This adds a new process_compilers_late method to the BuildTarget class,
which is evaluated after process_kwargs is called. This is needed
because some D options need to be evaluated after compilers are
selected, while for C-like languages we need to check the link* targets
for language requirements, and link* targets are passed by kwargs.
This implementation is recursive, since each Target adds it's parent's
dependencies.
Currently if a target uses link_whole, and one of those archives is a
C++, but the files for the target are C linking will fail when the C
linker attempts to link the C++ files. This patches add
link_whole_targets to the list of languages in the target so the correct
linker will be selected.
Commit 325a231a added stricter keyword argument checking, but didn't enable
keyword arguments for add_projects_link_arguments() and
add_global_link_arguments(). This makes them fail with this error:
Meson encountered an error in file meson.build, line 19, column 0:
Function does not take keyword arguments.
However, the language argument is required. Removing it produces this error
instead:
Meson encountered an error in file meson.build, line 19, column 0:
Missing language definition in add_project_link_arguments
Fix this by adding 'language' as a required keyword argument. Also add calls to
these in the "146 C and CPP link" test case.
VS2015 automatically picks up outputs from CustomBuild commands, which we
now use instead of CustomBuildStep commands, which do not get picked up
automatically.
Jussi Pakkanen
Nirbheek Chauhan
Dylan Baker
Aaron Plattner
Nirbheek Chauhan
Nicolas Schneider