The install directory contains the BUILD logic for creating an
installable tree of data files and executables for the toolchain, and
a library to facilitate toolchain code accessing the paths to their data
within this installation.
Then adds an installation of LLD in a synthetic LLVM installation, and
teaches the Clang runner to configure this and use it for linking
instead of the system linker.
Currently, the install paths only really manage access to the LLVM
binaries installed and used by the Clang runner for linking, but
eventually other data files like the prelude and runtime libraries will
be fleshed out as well. There are TODOs for moving more things over here
such as the prelude.
One interesting aspect of this is where to put helpers like parts of
LLVM in our install. This PR suggests nesting those files under
`lib/carbon`. While using a `lib` subdirectory isn't a perfect fit for
the FHS (Filesystem Hierarchy Standard), having a single location where
private data is collected is significantly superior to spreading them
across the system. This also matches similar patterns used by Clang
itself and several other language toolchains and standard libraries.
The install directory also provides a natural place for us to build out
packaging rules to create installable packages in various formats, but
that remains future work.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
This adds the most rudimentary support for linking in the Carbon driver
by calling out to the Clang driver and letting it do the linking. This
is a super minimal version to start with, just enough to be somewhat
useful and to exercise calling into Clang for this.
Also adds a Clang runner to help run the Clang driver. This is a bit
more complete, although it sill needs some significant work. For
example, it will need some significant enhancements to be able to
compile C++ code, etc.
One thing that will likely change here is to better manage streams and
work better as a library. For now, this is a bit limited because Clang
and LLVM don't provide the necessary support for this.