This patch removes the implicit build of all shared libraries a target
depends on. Targets only depend on the respective ABIs instead. This
alleviates the need to locally build complex shared libraries (think of
Qt) when developing applications. Instead, application developers can
use binary depot archives.
The implementation splits the mk/lib.mk file into three files:
- mk/a.mk for building one static library (.lib.a)
- mk/so.mk for building one shared object (.lib.so)
- mk/abi.mk for building one ABI stub (.abi.so)
Furthermore, the commit moves messages and the collection of build
artifacts to var/libdeps, triggers the build of kernel-specific
ld-<kernel>.lib.so, and prunes the lib-dependency tree at ABIs.
Fixes#5061
The depot tool 'build_bin_archive' used to ask only whether CCACHE is empty or
not and, if it wasn't empty, the tool added 'CCACHE := yes' to the build.conf
of the temporary build dir. This caused the sub-build processes to use ccache
even when the top-level CCACHE variable was set to a bogus value.
Also adds documentation of the CCACHE variable to the help message of the
'build' and 'build_bin_archive' tool.
Ref #4212
This commit complements issue #4004 with support for the depot/create
tool. If CCACHE=1 is specified at the command line, the build directory
for building a binary archive is configured with 'CCACHE := yes'.
This patch changes the depot layout such that each archive is
represented as a directory that contains the versions of the archive as
subdirectories.
Issue #2610
When building with multiple jobs, the 'Makefile' rule may be executed
before any of its sibling rules, which implicitly create the target
directory. In this case, the attempt to create the symlink for
'Makefile' fails and the 'build_bin_archive' aborts. Analogously to the
sibling rules, this fix creates the target directory as a side effect of
the 'Makefile' rule.
