# How to install Swift once it's built? **URL:** \ **Category:** Using Swift\ **Created:** [July 16, 2020, 8:53am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493 "2020-07-16T08:53:59Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 16, 2020, 8:53am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/1 "2020-07-16T08:53:59Z")
So I built Swift from source on Linux with `utils/build-script --release-debuginfo --install-swiftpm true -j8` but after it finished, it had not installed `swift` into `/usr/bin` or anything else. Instead everything was nested in a build folder. How can I install it into the base directories of Linux? Is there a script included in the Swift repo to do that, or an argument I need to pass to the build script? Thanks. ---
**Author:** ![Finagolfin](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/finagolfin/32/34388_2.png) [@Finagolfin](https://forums.swift.org/u/Finagolfin)\ **Post date:** [July 16, 2020, 2:52pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/2 "2020-07-16T14:52:49Z")
It's not well-documented, but adding `--install-destdir` will do what you want. The README notes that you can learn a lot by running `utils/build-script -h`, it's listed in there. You may need to patch the install a bit based on your distro layout and installed packages though, as [the Fedora packager had to](https://forums.swift.org/t/swift-5-2-1-on-fedora-where-were-at-and-a-request-for-help/35039). Alternately, the `--install-swiftpm` flag will have already put everything in a `build/Ninja-Release/toolchain-linux-x86_64` directory, from which you can just manually copy all non-conflicting files to `/usr`. It isn't an easy process yet, given that Swift builds its own clang that could conflict with an installed clang, so you're probably best off using the Swift toolchain you built from your home directory, by adding that toolchain folder to your path. ---
**Author:** ![Ron\_Olson](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ron_olson/32/1325_2.png) [@Ron\_Olson](https://forums.swift.org/u/Ron_Olson)\ **Post date:** [July 16, 2020, 3:01pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/3 "2020-07-16T15:01:49Z")
I'm the person who packages Swift for Fedora/RHEL/CentOS and if you're building it yourself, I recommend installing swift in `/usr/local/swift` and adding `/usr/local/swift/bin/` to your path, _after_ `/usr/bin`. The reason, as @Finagolfin mentions, is that, since you built your own copy of Swift, you already have `clang` installed, probably in `/usr/bin` and you don't want the Swift-specific version to override the system one. One thing I have come to appreciate, after fighting it so hard for a very long time (also mentioned by Buttaface), is that the Swift toolchain/directory is completely self-contained, executables look for other executables in the same directory so it's completely valid to put the swift directory (comprised of `bin`, `lib`, etc.) _anywhere you like_ and so long as the path is set, you can build Swift apps, use the REPL, etc. In Fedora I ended up installing the Swift toolchain under `/usr/libexec/swift` with symlinks of `swift`, `swiftc`, and `sourcekit-lsp` in `/usr/bin` and it works great, especially using SourceKit with Vim/VS Code. ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 16, 2020, 4:04pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/4 "2020-07-16T16:04:21Z")
Great, thanks for all the info. I built it on CentOS 7, and it's been quite the adventure! It's reassuring to hear I'm not the only one who might describe it as, "fighting it so hard for a very long time" 😅. So to be clear @Ron_Olson, you added `--install-dest-dir /usr/libexec/swift` to the build-script args? ---
**Author:** ![Ron\_Olson](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ron_olson/32/1325_2.png) [@Ron\_Olson](https://forums.swift.org/u/Ron_Olson)\ **Post date:** [July 16, 2020, 4:08pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/5 "2020-07-16T16:08:12Z")
You can take whatever you need (if anything now 😂) from [https://github.com/tachoknight/swift-lang-packaging-fedora](https://github.com/tachoknight/swift-lang-packaging-fedora); it’s all my scripts and patches and random stuff to make Swift work; there’s a swift-5.3 branch that I’m working with now in case you’d like to use any of that. ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 18, 2020, 12:52am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/6 "2020-07-18T00:52:41Z")
I don't see anything helpful at the link you sent. I'm still having trouble to understand the difference between the following options: ```swift --install-prefix PATH The installation prefix. This is where built Swift products (like bin, lib, and include) will be installed. --install-destdir PATH the path to use as the filesystem root for the installation ``` I added `--install-destdir` to my build-script command and _literally it did nothing at all differently than before_. Please advise. ---
**Author:** ![Finagolfin](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/finagolfin/32/34388_2.png) [@Finagolfin](https://forums.swift.org/u/Finagolfin)\ **Post date:** [July 18, 2020, 5:29pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/7 "2020-07-18T17:29:18Z")
> I don't see anything helpful at the link you sent. That's probably because [he uses](https://github.com/tachoknight/swift-lang-packaging-fedora/blob/master/swift-lang.spec#L173) a [build preset](https://github.com/apple/swift/blob/master/utils/build_swift/build_swift/driver_arguments.py#L1275). > I'm still having trouble to understand the difference The second is the sysroot, usually `/` but could be `/opt` or whatever, and the first is an optional prefix within the sysroot, usually `/usr`. If simply adding destdir to the build command you had before, I'm guessing you need to `--reconfigure` also. You're probably best off using one of the build presets detailed in that second doc link, as most people do. At the very least, the list of build presets give you common flag bundles to try out and customize, if you really need to. ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 18, 2020, 5:55pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/8 "2020-07-18T17:55:22Z")
Ah, sweet! Thanks @Finagolfin that cleared it up for me! Happy to report a working Swift build on CentOS 7. One question for @Ron_Olson: your repo specifies "buildbot\_linux"--where is that defined? Can't seem to find the definition in your repo, and when I try this command it fails. ---
**Author:** ![Ron\_Olson](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ron_olson/32/1325_2.png) [@Ron\_Olson](https://forums.swift.org/u/Ron_Olson)\ **Post date:** [July 18, 2020, 8:20pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/9 "2020-07-18T20:20:18Z")
> [@1oo7](#): > > your repo specifies "buildbot\_linux"--where is that defined? It's actually a preset in `swift/utils/build-presets.ini`. It defines what actually gets built and tested (e.g. no point trying to test Swift for WatchOS on Linux 🤣). ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 18, 2020, 9:52pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/10 "2020-07-18T21:52:11Z")
> [@Ron\_Olson](#): > > swift/utils/build-presets.ini I wonder why it's not working for me... hmm. Which line is it declared on? And is it in Swift 5.2.4? ---
**Author:** ![Ron\_Olson](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/ron_olson/32/1325_2.png) [@Ron\_Olson](https://forums.swift.org/u/Ron_Olson)\ **Post date:** [July 18, 2020, 9:57pm UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/11 "2020-07-18T21:57:30Z")
For 5.2.4 `buildbot_linux` is declared on line 772 in build-presets.ini ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 19, 2020, 1:31am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/12 "2020-07-19T01:31:35Z")
OK maybe I had a typo, will try the `buildbot_linux` and see if that works... ... because oddly, this command does _not_ result in the build products being installed at the prefix: ```swift utils/build-script --release-debuginfo \ --install-swiftpm true \ --install-destdir / \ --install-prefix /usr \ --reconfigure -j8 ``` I wonder if perhaps it needs to be: ```swift utils/build-script --release-debuginfo \ --install-swiftpm=true \ --install-destdir="/" \ --install-prefix="/usr" \ --reconfigure -j8 ``` ? The documentation doesn't specify that the = sign is required for setting parameters but, it's the only reason I can think of why the commands wouldn't work. ---
**Author:** ![1oo7](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/1oo7/32/17598_2.png) [@1oo7](https://forums.swift.org/u/1oo7)\ **Post date:** [July 20, 2020, 12:12am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/13 "2020-07-20T00:12:42Z")
So I tried this command: ```swift utils/build-script --preset=buildbot_linux,no_test install_destdir=/usr -j8 ``` But I get this error: ```swift utils/build-script: fatal error: no value found for installable_package in "%(installable_package)s" ``` I noticed in @Ron_Olson's script a value is given for `installable_package`... but for my use case, I'm not trying to create an "installable package"—I'm just trying to build and install Swift compiler and Swift package manager on the same system that I'm building on. Is there an existing script command will automatically install Swift using /usr as the root of the installation, so that for example, we will have /usr/bin/swift etc.? Sorry I'm asking so many questions but I can't get the buildbot to work, and none of the commands listed above seem to do the trick either. If the only way to install Swift is to write a secondary script that runs after the build process, which manually copies it out of the build folders, then I'll do that. But I guess I was expecting to be able to do something like "make install" and it would "just work". Thanks for any help. ---
**Author:** ![Finagolfin](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/finagolfin/32/34388_2.png) [@Finagolfin](https://forums.swift.org/u/Finagolfin)\ **Post date:** [July 24, 2020, 6:33am UTC](https://forums.swift.org/t/how-to-install-swift-once-its-built/38493/14 "2020-07-24T06:33:31Z")
It cannot "just work" because Swift builds specific versions, sometimes locally forked, of ICU, lldb, clang, and so on. Many people have those already installed in `/usr/bin`, so it is up to you to decide how to resolve those conflicts, if they exist. If you don't want an installable package, simply build it but don't use it or you can modify `build-presets.ini` to not require it, as Ben mentioned in another thread. Most of your questions are answered by carefully looking at the examples and config files in the documentation links I've linked you above. There are some aspects that are unintuitive, so you can ask about those here.