On macOS, we set the install_name for built libraries to
@rpath/libfoo.dylib, and when linking to the library, we set the RPATH
to its path in the build directory. This allows all built binaries to
be run as-is from the build directory (uninstalled).
However, on install, we have to strip all the RPATHs because they
point to the build directory, and we change the install_name of all
built libraries to the absolute path to the library. This causes the
install name in binaries to be out of date.
We now change that install name to point to the absolute path to each
built library after installation.
Fixes https://github.com/mesonbuild/meson/issues/3038
Fixes https://github.com/mesonbuild/meson/issues/3077
With this, the default workflow on macOS matches what everyone seems
to do, including Autotools and CMake. The next step is providing a way
for build files to override the install_name that is used after
installation for use with, f.ex., private libraries when combined with
the install_rpath: kwarg on targets.
When we link to an external library either with find_library() without
any dirs:, or with dependency(), we should be able to run uninstalled
out of the box without having to set any environment variables or other
shenanigans.
This is especially important on macOS because only the system frameworks
directory is in the default runtime path, and all other frameworks and
libraries need to be found with RPATH or absolute path to the dylib.
Jussi Pakkanen
Nirbheek Chauhan