This commit optimizes the compile time for creating tarballs of cross-host
compilers and as a proof of concept adds two to the standard Travis matrix. Much
of this commit is further refactoring and refining of the `step.rs` definitions
along with the interpretation of `--target` and `--host` flags. This has gotten
confusing enough that I've also added a small test suite to
`src/bootstrap/step.rs` to ensure what we're doing works and doesn't regress.
After this commit when you execute:
./x.py dist --host $MY_HOST --target $MY_HOST
the build system will compile two compilers. The first is for the build platform
and the second is for the host platform. This second compiler is then packaged
up and placed into `build/dist` and is ready to go. With a fully cached LLVM and
docker image I was able to create a cross-host compiler in around 20 minutes
locally.
Eventually we plan to add a whole litany of cross-host entries to the Travis
matrix, but for now we're just adding a few before we eat up all the extra
capacity.
cc #38531
The source tarball creation step would attempt to skip a number of files that we
want to ignore ourselves, but once we've hit the vendor directory we don't want
to skip anything so be sure to vendor everything inside that directory.
Closes#38690
This commit skips a few more dist tragets during compilation which shouldn't be
necessary.
* First, when packaging std we only take action when the host target is the
build target. Otherwise we package the same artifacts a number of times, which
shouldn't be necessary.
* Next, we apply the same logic to the save-analysis build. This is actually
required for correctness as the build compiler is the only one which actually
has save analysis information. This should fix an error seen on nightlies.
Git worktrees have this as a file and typically won't work inside docker
containers, but that's ok, so instead of just checking for existence check for a
directory to see if the git commands will succeed.
This commit implements the `distcheck` target for rustbuild which is only ever
run on our nightly bots. This essentially just creates a tarball, un-tars it,
and then runs a full build, validating that the release tarballs do indeed have
everything they need to build Rust.
As the entry point for building the Rust compiler, a good user experience hinges
on this compiling quickly to get to the meat of the problem. To that end use
`#[cfg]`-specific dependencies to avoid building Windows crates on Unix and drop
the `regex` crate for now which was easily replacable with some string
searching.
The organization in rustbuild was a little odd at the moment where the `lib.rs`
was quite small but the binary `main.rs` was much larger. Unfortunately as well
there was a `build/` directory with the implementation of the build system, but
this directory was ignored by GitHub on the file-search prompt which was a
little annoying.
This commit reorganizes rustbuild slightly where all the library files (the
build system) is located directly inside of `src/bootstrap` and all the binaries
now live in `src/bootstrap/bin` (they're small). Hopefully this should allow
GitHub to index and allow navigating all the files while maintaining a
relatively similar layout to the other libraries in `src/`.
