My personal hacked together script for building a completely self-contained Emacs.app application on macOS, from any git branch, tag, or ref. With support for native-compilation.
Use this script at your own risk.
- To use new features available from master or branches, which have not made it into a official stable release yet.
- Homebrew builds of Emacs are not self-contained applications, making it very difficult when doing HEAD builds and you need to rollback to a earlier version.
- Both Homebrew HEAD builds, and nightly builds from emacsformacosx.com are
built from the
masterbranch. This script allows you to choose any branch, tag, or git ref you want.
Nightly and stable binary builds produced with this build script are available from jimeh/emacs-builds.
The build produced does have some limitations:
- It is not a universal application. The CPU architecture of the built application will be that of the machine it was built on.
- The minimum required macOS version of the built application will be the same as that of the machine it was built on.
- The application is not signed automatically, but the CLI tool used to sign the
nightly builds is available. Run
go run ./cmd/emacs-builder package --helpfor details. More detailed instructions will come soon.
- Xcode
- Homebrew
- All Homebrew formula listed in the
Brewfile, which can all easily be installed by running:brew bundle - Ruby 2.3.0 or later is needed to execute the build script itself. macOS comes
with Ruby, check your version with
ruby --version. If it's too old, you can install a newer version with:brew install ruby
As of writing (2021-11-27) it works for me on my machine and for the nightly builds in jimeh/emacs-builds. Your luck may vary.
I have successfully built:
emacs-28release branchmasterbranch (Emacs 29.x)
For reference, my machine is:
- 13-inch MacBook Pro (2020), 10th-gen 2.3 GHz Quad-Core Intel Core i7 (4c/8t)
- macOS Monterey 12.0.1 (21A559)
- Xcode 13.1 (13A1030d)
Nightly builds are built with GitHub Actions on GitHub-hosted runners, using
macos-10.15.
Usage: ./build-emacs-for-macos [options] <branch/tag/sha>
Branch, tag, and SHA are from the emacs-mirror/emacs/emacs Github repo,
available here: https://github.com/emacs-mirror/emacs
Options:
-j, --parallel COUNT Compile using COUNT parallel processes (detected: 8)
--git-sha SHA Override detected git SHA of specified branch allowing builds of old commits
--[no-]xwidgets Enable/disable XWidgets if supported (default: enabled)
--[no-]native-comp Enable/disable native-comp (default: enabled if supported)
--[no-]native-march Enable/disable -march=native CFLAG(default: disabled)
--[no-]native-full-aot Enable/disable NATIVE_FULL_AOT / Ahead of Time compilation (default: disabled)
--[no-]relink-eln-files Enable/disable re-linking shared libraries in bundled *.eln files (default: enabled)
--[no-]rsvg Enable/disable SVG image support via librsvg (default: enabled)
--no-titlebar Apply no-titlebar patch (default: disabled)
--posix-spawn Apply posix-spawn patch (default: disabled)
--no-frame-refocus Apply no-frame-refocus patch (default: disabled)
--[no-]github-auth Make authenticated GitHub API requests if GITHUB_TOKEN environment variable is set.(default: enabled)
--work-dir DIR Specify a working directory where tarballs, sources, and builds will be stored and worked with
-o, --output DIR Output directory for finished builds (default: <work-dir>/builds)
--build-name NAME Override generated build name
--dist-include x,y,z List of extra files to copy from Emacs source into build folder/archive (default: COPYING)
--[no-]archive Enable/disable creating *.tbz archive (default: enabled)
--[no-]archive-keep-build-dir
Enable/disable keeping source folder for archive (default: disabled)
--plan FILE Follow given plan file, instead of using given git ref/sha
Resulting applications are saved to the builds directory in a bzip2 compressed
tarball.
If you don't want the build process to eat all your CPU cores, pass in a -j
value of how many CPU cores you want it to use.
Re-building the same Git SHA again can yield weird results unless you first
trash the corresponding directory from the sources directory.
To download a tarball of the master branch (Emacs 28.x with native-compilation
as of writing) and build Emacs.app from it:
./build-emacs-for-macos
To build the stable emacs-27.1 release git tag run:
./build-emacs-for-macos emacs-27.1
All sources as downloaded as tarballs from the emacs-mirror GitHub repository. Hence to get a list of tags/branches available to install, simply check said repository.
Builds come with a custom emacs shell script launcher for use from the command
line, located next to emacsclient in Emacs.app/Contents/MacOS/bin.
The custom emacs script makes sure to use the main
Emacs.app/Contents/MacOS/Emacs executable from the correct path, ensuring it
finds all the relevant dependencies within the Emacs.app bundle, regardless of
it it's exposed via PATH or symlinked to from elsewhere.
To use it, simply add Emacs.app/Contents/MacOS/bin to your PATH. For
example, if you place Emacs.app in /Applications:
if [ -d "/Applications/Emacs.app/Contents/MacOS/bin" ]; then
export PATH="/Applications/Emacs.app/Contents/MacOS/bin:$PATH"
alias emacs="emacs -nw" # Always launch "emacs" in terminal mode.
fiIf you want emacs in your terminal to launch a GUI instance of Emacs, don't
use the alias from the above example.
Note: On 2021-04-25 the feature/native-comp branch was
merged
into master.
The build script will automatically detect if the source tree being built
supports native-compilation, and enable it if available. You can override the
auto-detection logic to force enable or force disable native-compilation by
passing --native-comp or --no-native-comp respectfully.
By default NATIVE_FULL_AOT is disabled which ensures a fast build by native
compiling as few elisp source files as possible to build Emacs itself. Any
remaining elisp files will be dynamically compiled in the background the first
time they are used.
To enable native full Ahead-of-Time compilation, pass in the --native-full-aot
option, which will native-compile all of Emacs' elisp at built-time. On my
machine it takes around 10 minutes to build Emacs.app with NATIVE_FULL_AOT
disabled, and around 20-25 minutes with it enabled.
By default natively compiled *.eln files will be cached in
~/.emacs.d/eln-cache/. If you want to customize that, simply set a new path as
the first element of the native-comp-eln-load-path variable. The path string
must end with a /.
Below is an example which stores all compiled *.eln files in cache/eln-cache
within your Emacs configuration directory:
(when (boundp 'native-comp-eln-load-path)
(setcar native-comp-eln-load-path
(expand-file-name "cache/eln-cache/" user-emacs-directory)))By default any warnings encountered during async native compilation will pop up
a warnings buffer. As this tends to happen rather frequently with a lot of
packages, it can get annoying. You can disable showing these warnings by setting
native-comp-async-report-warnings-errors to nil:
(setq native-comp-async-report-warnings-errors nil)Please see all issues with the
native-comp
label. It's a good idea if you read through them so you're familiar with the
types of issues and or behavior you can expect.
A list of known "good" commits which produce working builds is tracked in: #6 Known good commits for native-comp
- I've borrowed some ideas from David Caldwell's excellent build-emacs project, which produces all builds for emacsformacosx.com.
- Patches applied are pulled from emacs-plus, which is an excellent Homebrew formula with lots of options not available elsewhere.
- The following sources were extremely useful in figuring out how get get the
feature/native-compbranch building on macOS:
The script downloads the source code as a gzipped tar archive from the GitHub mirror repository, as it makes it very easy to get a tarball of any given git reference.
It then runs ./configure with a various options, including copying various
dynamic libraries into the application itself. So the built application should
in theory run on a macOS install that does not have Homebrew, or does not have
the relevant Homebrew formulas installed.
Code quality of the script itself, is well, non-existent. The build script started life a super-quick hack back in 2013, and now it's even more of a dirty hack. I might clean it up and add unit tests if I end up relying on this script for a prolonged period of time. For now I plan to use it at least until native-comp lands in a stable Emacs release for macOS.