We use bazel
1 to build Vere, which is packaged as a single binary,
urbit
. We support the following (host, target)
pairs, where the host platform
is where bazel
runs and the target platform is where urbit
will
run:
Host Platform | Target Platform |
---|---|
linux-aarch64 |
linux-aarch64 |
linux-x86_64 |
linux-x86_64 |
macos-aarch64 |
macos-aarch64 |
macos-x86_64 |
macos-x86_64 |
The first step is to install bazel
using the instructions found on the bazel
1 site.
All platforms require the automake
and libtool
suite of tools installed in
order to build Vere. Before going any further, install them using your package
manager. For example, on macOS:
brew install automake libtool
After installing automake
and libtool
, you need to install the musl libc toolchain. We use musl libc instead of glibc on Linux, which enables us to generate statically linked binaries. As a prerequisite, you need to install the musl libc toolchain appropriate for your target platform.
To install the x86_64-linux-musl-gcc
toolchain at
/usr/local/x86_64-linux-musl-gcc
, run:
bazel run //bazel/toolchain:x86_64-linux-musl-gcc
This will take a few minutes.
To install the aarch64-linux-musl-gcc
toolchain at
/usr/local/aarch64-linux-musl-gcc
, run:
bazel run //bazel/toolchain:aarch64-linux-musl-gcc
This will take a few minutes.
After installing automake
and libtool
, you're ready to build Vere.
Once you install the prerequisites, you're ready to build:
bazel build :urbit
If you want a debug build, which changes the optimization level from -O3
to
-O0
and includes more debugging information, specify the dbg
configuration:
bazel build --config=dbg :urbit
Note that you cannot change the optimization level for third party
dependencies--those targets specified in bazel/third_party
--from the command
line.
You can turn on CPU and memory debugging by defining U3_CPU_DEBUG
and
U3_MEMORY_DEBUG
, respectively:
bazel build --copt='-DU3_CPU_DEBUG' --copt='-DU3_MEMORY_DEBUG' :urbit
Note that defining these two debug symbols will produce ships that are incompatible with binaries without these two debug symbols defined.
If you need to specify arbitrary C compiler or linker options, use
--copt
or --linkopt
, respectively:
bazel build --copt='-O0' :urbit
Note --copt
can be used to specify any C compiler options, not just
optimization levels.
You can build and run unit tests only on native builds. If you have a native build and want to run all unit tests, run:
bazel test --build_tests_only ...
If you want to run a specific test, say
pkg/noun/hashtable_tests.c
, run:
bazel test //pkg/noun:hashtable_tests
Any options you specify at the command line can instead be specified in
.user.bazelrc
if you find yourself using the same options over and over. This
file is not tracked by git
, so whatever you add to it will not affect anyone
else. As an example, if you want to change the optimization level but don't want
type --copt='-O0'
each time, you can do the following:
echo "build --copt='-O0'" >> .user.bazelrc
bazel build :urbit
For more information on Bazel configuration files, consult the Bazel docs.
If bazel build
or bazel test
generates an undeclared inclusion(s) in rule
error on macOS, the version of clang
expected by the build system likely
doesn't match the version of clang
installed on your system. To address this,
run clang --version
and pass the version number via
--clang_version="<version_string>"
to the failing command.
Footnotes
-
If you're interested in digging into the details of the build system, check out
WORKSPACE.bazel
,BUILD.bazel
,bazel/
, and the multipleBUILD.bazel
files inpkg/
. ↩ ↩2