Add a boolean 'implib' kwarg to executable(). If true, it is permitted to
use the returned build target object in link_with:
On platforms where this makes sense (e.g. Windows), an implib is generated
for the executable and used when linking. Otherwise, it has no effect.
(Rather than checking if it is a StaticLibrary or SharedLibary, BuildTarget
subclasses gain the is_linkable_target method to test if they can appear in
link_with:)
Also install any executable implib in a similar way to a shared library
implib, i.e. placing the implib in the appropriate place
Add tests of:
- a shared_module containing a reference to a symbol which is known (at link
time) to be provided by the executable
- trying to link with non-implib executables (should fail)
- installing the implib
(This last one needs a little enhancement of the installed file checking as
this is the first install test we have which needs to work with either
MSVC-style or GCC-style implib filenames)
- Adds a `crate_type` kwarg to library targets, allowing the different
types of Rust [linkage][1].
- Shared libraries use the `dylib` crate type by default, but can also
be `cdylib`
- Static libraries use the `rlib` crate type by default, but can also
be `staticlib`
- If any Rust target has shared library dependencies, add the
appropriate linker arguments, including rpath for the sysroot of the
Rust compiler
[1]: https://doc.rust-lang.org/reference/linkage.html
This is useful when build_machine appears to be compatible with
host_machine, but actually isn't. For example when:
- build_machine is macOS and host_machine is the iOS Simulator
- the build_machine's libc is glibc but the host_machine libc is uClibc
- code relies on kernel features not available on the build_machine