Swift on FreeBSD

Matt Jacobson
November 2022 (updated March 2023)

Swift is officially supported on Darwin, Linux, and Windows. Some people have put in work to get it running on FreeBSD and OpenBSD, but over time the FreeBSD port succumbed to bit rot.

In October 2022, I started working on getting the FreeBSD port working again. I'm going to try something new where I attempt to use a blog entry for my project notes, with the hopes that it'll force me to organize them better.

This document is likely incomplete and incorrect. Last updated: Mar. 16, 2023.

Completed work

Build system fix in configure_unix_sdk; PR merged
~~Workaround for <unwind.h> craziness; PR~~ abandoned
Build fix in swift-dependency-tool; PR merged
Define CLongDouble; PR merged
Define RTLD_DEFAULT; PR merged
Another build system fix in configure_unix_sdk; PR merged
Use lld, not gold; PR merged, swift-driver PR merged
Fix bootstrapped build; PR merged
~~Don't pass -nostdsysteminc in ClangImporter; PR~~ abandoned in favor of LLVM change
Fix FreeBSD build in lib/Threading; PR merged
Recognize amd64 in CMAKE_SYSTEM_PROCESSOR (minor); PR merged
Fix build of SwiftReflectionTest; PR merged
Install SwiftGlibc.h in swift_static resources; PR merged
Set rpath of stdlib dylibs to $ORIGIN; PR
Implement clock functions; PR merged
Move clang include path management from frontend to driver; patch accepted, apple/llvm-project cherry-pick merged
Fix implicit _Concurrency import; PR merged
Fix rebranch build failure (post-5.8); PR
Implement POSIXErrorCode; PR merged

Work in progress

Float methods use LLVM intrinsics like @llvm.round, which require libm, which is not linked; patch prepared
Changes to libdispatch to make it build on FreeBSD (again)
Changes to Foundation to make it build on FreeBSD
Fix various unit tests on FreeBSD

This stuff will be updated on an ongoing basis:

A docs page on how to build on FreeBSD
A ports tree entry
~~Swift 5.7 + FreeBSD fixes branch~~ no longer maintained

Future directions

Add swift-driver to build
SwiftPM