Building Julia (Detailed)
Downloading the Julia source code
If you are behind a firewall, you may need to use the https
protocol instead of the git
protocol:
git config --global url."https://".insteadOf git://
Be sure to also configure your system to use the appropriate proxy settings, e.g. by setting the https_proxy
and http_proxy
variables.
Building Julia
When compiled the first time, the build will automatically download pre-built external dependencies. If you prefer to build all the dependencies on your own, or are building on a system that cannot access the network during the build process, add the following in Make.user
:
USE_BINARYBUILDER=0
Building Julia requires 5GiB if building all dependencies and approximately 4GiB of virtual memory.
To perform a parallel build, use make -j N
and supply the maximum number of concurrent processes. If the defaults in the build do not work for you, and you need to set specific make parameters, you can save them in Make.user
, and place the file in the root of your Julia source. The build will automatically check for the existence of Make.user
and use it if it exists.
You can create out-of-tree builds of Julia by specifying make O=<build-directory> configure
on the command line. This will create a directory mirror, with all of the necessary Makefiles to build Julia, in the specified directory. These builds will share the source files in Julia and deps/srccache
. Each out-of-tree build directory can have its own Make.user
file to override the global Make.user
file in the top-level folder.
If everything works correctly, you will see a Julia banner and an interactive prompt into which you can enter expressions for evaluation. (Errors related to libraries might be caused by old, incompatible libraries sitting around in your PATH. In this case, try moving the julia
directory earlier in the PATH). Note that most of the instructions above apply to unix systems.
To run julia from anywhere you can:
add an alias (in
bash
:echo "alias julia='/path/to/install/folder/bin/julia'" >> ~/.bashrc && source ~/.bashrc
), oradd a soft link to the
julia
executable in thejulia
directory to/usr/local/bin
(or any suitable directory already in your path), oradd the
julia
directory to your executable path for this shell session (inbash
:export PATH="$(pwd):$PATH"
; incsh
ortcsh
:
set path= ( $path $cwd )
), or
add the
julia
directory to your executable path permanently (e.g. in.bash_profile
), orwrite
prefix=/path/to/install/folder
intoMake.user
and then runmake install
. If there is a version of Julia already installed in this folder, you should delete it before runningmake install
.
Some of the options you can set to control the build of Julia are listed and documented at the beginning of the file Make.inc
, but you should never edit it for this purpose, use Make.user
instead.
Julia's Makefiles define convenient automatic rules called print-<VARNAME>
for printing the value of variables, replacing <VARNAME>
with the name of the variable to print the value of. For example
$ make print-JULIA_PRECOMPILE
JULIA_PRECOMPILE=1
These rules are useful for debugging purposes.
Now you should be able to run Julia like this:
julia
If you are building a Julia package for distribution on Linux, macOS, or Windows, take a look at the detailed notes in distributing.md.
Updating an existing source tree
If you have previously downloaded julia
using git clone
, you can update the existing source tree using git pull
rather than starting anew:
cd julia
git pull && make
Assuming that you had made no changes to the source tree that will conflict with upstream updates, these commands will trigger a build to update to the latest version.
General troubleshooting
Over time, the base library may accumulate enough changes such that the bootstrapping process in building the system image will fail. If this happens, the build may fail with an error like
*** This error is usually fixed by running 'make clean'. If the error persists, try 'make cleanall' ***
As described, running
make clean && make
is usually sufficient. Occasionally, the stronger cleanup done bymake cleanall
is needed.New versions of external dependencies may be introduced which may occasionally cause conflicts with existing builds of older versions.
a. Special
make
targets exist to help wipe the existing build of a dependency. For example,make -C deps clean-llvm
will clean out the existing build ofllvm
so thatllvm
will be rebuilt from the downloaded source distribution the next timemake
is called.make -C deps distclean-llvm
is a stronger wipe which will also delete the downloaded source distribution, ensuring that a fresh copy of the source distribution will be downloaded and that any new patches will be applied the next timemake
is called.b. To delete existing binaries of
julia
and all its dependencies, delete the./usr
directory in the source tree.If you've updated macOS recently, be sure to run
xcode-select --install
to update the command line tools. Otherwise, you could run into errors for missing headers and libraries, such asld: library not found for -lcrt1.10.6.o
.If you've moved the source directory, you might get errors such as
CMake Error: The current CMakeCache.txt directory ... is different than the directory ... where CMakeCache.txt was created.
, in which case you may delete the offending dependency underdeps
In extreme cases, you may wish to reset the source tree to a pristine state. The following git commands may be helpful:
git reset --hard #Forcibly remove any changes to any files under version control git clean -x -f -d #Forcibly remove any file or directory not under version control
To avoid losing work, make sure you know what these commands do before you run them.
git
will not be able to undo these changes!
Platform-Specific Notes
Notes for various operating systems:
Notes for various architectures:
Required Build Tools and External Libraries
Building Julia requires that the following software be installed:
- [GNU make] — building dependencies.
- [gcc & g++][gcc] (>= 7.1) or [Clang][clang] (>= 5.0, >= 9.3 for Apple Clang) — compiling and linking C, C++.
- [libatomic][gcc] — provided by [gcc] and needed to support atomic operations.
- [python] (>=2.7) — needed to build LLVM.
- [gfortran] — compiling and linking Fortran libraries.
- [perl] — preprocessing of header files of libraries.
- [wget], [curl], or [fetch] (FreeBSD) — to automatically download external libraries.
- [m4] — needed to build GMP.
- [awk] — helper tool for Makefiles.
- [patch] — for modifying source code.
- [cmake] (>= 3.4.3) — needed to build
libgit2
. - [pkg-config] — needed to build
libgit2
correctly, especially for proxy support. - [powershell] (>= 3.0) — necessary only on Windows.
- [which] — needed for checking build dependencies.
On Debian-based distributions (e.g. Ubuntu), you can easily install them with apt-get
:
sudo apt-get install build-essential libatomic1 python gfortran perl wget m4 cmake pkg-config curl
Julia uses the following external libraries, which are automatically downloaded (or in a few cases, included in the Julia source repository) and then compiled from source the first time you run make
. The specific version numbers of these libraries that Julia uses are listed in deps/$(libname).version
:
- [LLVM] (15.0 + patches) — compiler infrastructure (see note below).
- [FemtoLisp] — packaged with Julia source, and used to implement the compiler front-end.
- [libuv] (custom fork) — portable, high-performance event-based I/O library.
- [OpenLibm] — portable libm library containing elementary math functions.
- [DSFMT] — fast Mersenne Twister pseudorandom number generator library.
- [OpenBLAS] — fast, open, and maintained [basic linear algebra subprograms (BLAS)]
- [LAPACK] — library of linear algebra routines for solving systems of simultaneous linear equations, least-squares solutions of linear systems of equations, eigenvalue problems, and singular value problems.
- [MKL] (optional) – OpenBLAS and LAPACK may be replaced by Intel's MKL library.
- [SuiteSparse] — library of linear algebra routines for sparse matrices.
- [PCRE] — Perl-compatible regular expressions library.
- [GMP] — GNU multiple precision arithmetic library, needed for
BigInt
support. - [MPFR] — GNU multiple precision floating point library, needed for arbitrary precision floating point (
BigFloat
) support. - [libgit2] — Git linkable library, used by Julia's package manager.
- [curl] — libcurl provides download and proxy support.
- [libssh2] — library for SSH transport, used by libgit2 for packages with SSH remotes.
- [mbedtls] — library used for cryptography and transport layer security, used by libssh2
- [utf8proc] — a library for processing UTF-8 encoded Unicode strings.
- [LLVM libunwind] — LLVM's fork of [libunwind], a library that determines the call-chain of a program.
- [ITTAPI] — Intel's Instrumentation and Tracing Technology and Just-In-Time API.
[GNU make]: https://www.gnu.org/software/make [patch]: https://www.gnu.org/software/patch [wget]: https://www.gnu.org/software/wget [m4]: https://www.gnu.org/software/m4 [awk]: https://www.gnu.org/software/gawk [gcc]: https://gcc.gnu.org [clang]: https://clang.llvm.org [python]: https://www.python.org/ [gfortran]: https://gcc.gnu.org/fortran/ [curl]: https://curl.haxx.se [fetch]: https://www.freebsd.org/cgi/man.cgi?fetch(1) [perl]: https://www.perl.org [cmake]: https://www.cmake.org [OpenLibm]: https://github.com/JuliaLang/openlibm [DSFMT]: https://github.com/MersenneTwister-Lab/dSFMT [OpenBLAS]: https://github.com/xianyi/OpenBLAS [LAPACK]: https://www.netlib.org/lapack [MKL]: https://software.intel.com/en-us/articles/intel-mkl [SuiteSparse]: https://people.engr.tamu.edu/davis/suitesparse.html [PCRE]: https://www.pcre.org [LLVM]: https://www.llvm.org [LLVM libunwind]: https://github.com/llvm/llvm-project/tree/main/libunwind [FemtoLisp]: https://github.com/JeffBezanson/femtolisp [GMP]: https://gmplib.org [MPFR]: https://www.mpfr.org [libuv]: https://github.com/JuliaLang/libuv [libgit2]: https://libgit2.org/ [utf8proc]: https://julialang.org/utf8proc/ [libunwind]: https://www.nongnu.org/libunwind [libssh2]: https://www.libssh2.org [mbedtls]: https://tls.mbed.org/ [pkg-config]: https://www.freedesktop.org/wiki/Software/pkg-config/ [powershell]: https://docs.microsoft.com/en-us/powershell/scripting/wmf/overview [which]: https://carlowood.github.io/which/ [ITTAPI]: https://github.com/intel/ittapi
Build dependencies
If you already have one or more of these packages installed on your system, you can prevent Julia from compiling duplicates of these libraries by passing USE_SYSTEM_...=1
to make
or adding the line to Make.user
. The complete list of possible flags can be found in Make.inc
.
Please be aware that this procedure is not officially supported, as it introduces additional variability into the installation and versioning of the dependencies, and is recommended only for system package maintainers. Unexpected compile errors may result, as the build system will do no further checking to ensure the proper packages are installed.
LLVM
The most complicated dependency is LLVM, for which we require additional patches from upstream (LLVM is not backward compatible).
For packaging Julia with LLVM, we recommend either:
- bundling a Julia-only LLVM library inside the Julia package, or
- adding the patches to the LLVM package of the distribution.
- A complete list of patches is available in on Github see the
julia-release/18.x
branch. - The only Julia-specific patch is the lib renaming (
llvm7-symver-jlprefix.patch
), which should not be applied to a system LLVM. - The remaining patches are all upstream bug fixes, and have been contributed into upstream LLVM.
- A complete list of patches is available in on Github see the
Using an unpatched or different version of LLVM will result in errors and/or poor performance. You can build a different version of LLVM from a remote Git repository with the following options in the Make.user
file:
# Force source build of LLVM
USE_BINARYBUILDER_LLVM = 0
# Use Git for fetching LLVM source code
# this is either `1` to get all of them
DEPS_GIT = 1
# or a space-separated list of specific dependencies to download with git
DEPS_GIT = llvm
# Other useful options:
#URL of the Git repository you want to obtain LLVM from:
# LLVM_GIT_URL = ...
#Name of the alternate branch to clone from git
# LLVM_BRANCH = julia-16.0.6-0
#SHA hash of the alternate commit to check out automatically
# LLVM_SHA1 = $(LLVM_BRANCH)
#List of LLVM targets to build. It is strongly recommended to keep at least all the
#default targets listed in `deps/llvm.mk`, even if you don't necessarily need all of them.
# LLVM_TARGETS = ...
#Use ccache for faster recompilation in case you need to restart a build.
# USECCACHE = 1
# CMAKE_GENERATOR=Ninja
# LLVM_ASSERTIONS=1
# LLVM_DEBUG=Symbols
The various build phases are controlled by specific files:
deps/llvm.version
: touch or change to checkout a new version,make get-llvm check-llvm
deps/srccache/llvm/source-extracted
: result ofmake extract-llvm
deps/llvm/build_Release*/build-configured
: result ofmake configure-llvm
deps/llvm/build_Release*/build-configured
: result ofmake compile-llvm
usr-staging/llvm/build_Release*.tgz
: result ofmake stage-llvm
(regenerate withmake reinstall-llvm
)usr/manifest/llvm
: result ofmake install-llvm
(regenerate withmake uninstall-llvm
)make version-check-llvm
: runs every time to warn the user if there are local modifications
Though Julia can be built with newer LLVM versions, support for this should be regarded as experimental and not suitable for packaging.
libuv
Julia uses a custom fork of libuv. It is a small dependency, and can be safely bundled in the same package as Julia, and will not conflict with the system library. Julia builds should not try to use the system libuv.
BLAS and LAPACK
As a high-performance numerical language, Julia should be linked to a multi-threaded BLAS and LAPACK, such as OpenBLAS or ATLAS, which will provide much better performance than the reference libblas
implementations which may be default on some systems.
Source distributions of releases
Each pre-release and release of Julia has a "full" source distribution and a "light" source distribution.
The full source distribution contains the source code for Julia and all dependencies so that it can be built from source without an internet connection. The light source distribution does not include the source code of dependencies.
For example, julia-1.0.0.tar.gz
is the light source distribution for the v1.0.0
release of Julia, while julia-1.0.0-full.tar.gz
is the full source distribution.
Building Julia from source with a Git checkout of a stdlib
If you need to build Julia from source with a Git checkout of a stdlib, then use make DEPS_GIT=NAME_OF_STDLIB
when building Julia.
For example, if you need to build Julia from source with a Git checkout of Pkg, then use make DEPS_GIT=Pkg
when building Julia. The Pkg
repo is in stdlib/Pkg
, and created initially with a detached HEAD
. If you're doing this from a pre-existing Julia repository, you may need to make clean
beforehand.
If you need to build Julia from source with Git checkouts of more than one stdlib, then DEPS_GIT
should be a space-separated list of the stdlib names. For example, if you need to build Julia from source with a Git checkout of Pkg, Tar, and Downloads, then use make DEPS_GIT='Pkg Tar Downloads'
when building Julia.
Building an "assert build" of Julia
An "assert build" of Julia is a build that was built with both FORCE_ASSERTIONS=1
and LLVM_ASSERTIONS=1
. To build an assert build, define both of the following variables in your Make.user
file:
FORCE_ASSERTIONS=1
LLVM_ASSERTIONS=1
Please note that assert builds of Julia will be slower than regular (non-assert) builds.
Building 32-bit Julia on a 64-bit machine
Occasionally, bugs specific to 32-bit architectures may arise, and when this happens it is useful to be able to debug the problem on your local machine. Since most modern 64-bit systems support running programs built for 32-bit ones, if you don't have to recompile Julia from source (e.g. you mainly need to inspect the behavior of a 32-bit Julia without having to touch the C code), you can likely use a 32-bit build of Julia for your system that you can obtain from the official downloads page. However, if you do need to recompile Julia from source one option is to use a Docker container of a 32-bit system. At least for now, building a 32-bit version of Julia is relatively straightforward using ubuntu 32-bit docker images. In brief, after setting up docker
here are the required steps:
$ docker pull i386/ubuntu
$ docker run --platform i386 -i -t i386/ubuntu /bin/bash
At this point you should be in a 32-bit machine console (note that uname
reports the host architecture, so will still say 64-bit, but this will not affect the Julia build). You can add packages and compile code; when you exit
, all the changes will be lost, so be sure to finish your analysis in a single session or set up a copy/pastable script you can use to set up your environment.
From this point, you should
# apt update
(Note that sudo
isn't installed, but neither is it necessary since you are running as root
, so you can omit sudo
from all commands.)
Then add all the build dependencies, a console-based editor of your choice, git
, and anything else you'll need (e.g., gdb
, rr
, etc). Pick a directory to work in and git clone
Julia, check out the branch you wish to debug, and build Julia as usual.
Update the version number of a dependency
There are two types of builds
- Build everything (
deps/
andsrc/
) from source code. (AddUSE_BINARYBUILDER=0
toMake.user
, see Building Julia) - Build from source (
src/
) with pre-compiled dependencies (default)
When you want to update the version number of a dependency in deps/
, you may want to use the following checklist:
### Check list
Version numbers:
- [ ] `deps/$(libname).version`: `LIBNAME_VER`, `LIBNAME_BRANCH`, `LIBNAME_SHA1` and `LIBNAME_JLL_VER`
- [ ] `stdlib/$(LIBNAME_JLL_NAME)_jll/Project.toml`: `version`
Checksum:
- [ ] `deps/checksums/$(libname)`
- [ ] `deps/checksums/$(LIBNAME_JLL_NAME)-*/`: `md5` and `sha512`
Patches:
- [ ] `deps/$(libname).mk`
- [ ] `deps/patches/$(libname)-*.patch`
Note:
- For specific dependencies, some items in the checklist may not exist.
- For checksum file, it may be a single file without a suffix, or a folder containing two files.
Example: OpenLibm
- Update Version numbers in
deps/openlibm.version
OPENLIBM_VER := 0.X.Y
OPENLIBM_BRANCH = v0.X.Y
OPENLIBM_SHA1 = new-sha1-hash
- Update Version number in
stdlib/OpenLibm_jll/Project.toml
version = "0.X.Y+0"
- Update checksums in
deps/checksums/openlibm
make -f contrib/refresh_checksums.mk openlibm
- Check if the patch files
deps/patches/openlibm-*.patch
exist- if patches don't exist, skip.
- if patches exist, check if they have been merged into the new version and need to be removed. When deleting a patch, remember to modify the corresponding Makefile file (
deps/openlibm.mk
).