Visual Studio 2017 or newer is needed to build Swift on Windows. The free Community edition is sufficient to build Swift.
The commands below (with the exception of installing Visual Studio) must be entered in the "x64 Native Tools Command Prompt for VS2017" (or VS2019, VS2019 Preview depending on the Visual Studio that you are using) in the Start Menu. This sets environment variables to select the correct target platform.
An easy way to get most of the tools to build Swift is using the Visual Studio installer. This command installs all needed Visual Studio components as well as Python, Git, CMake and Ninja:
curl.exe -sOL https://aka.ms/vs/16/release/vs_community.exe
vs_community ^
--add Component.CPython3.x64 ^
--add Microsoft.VisualStudio.Component.Git ^
--add Microsoft.VisualStudio.Component.VC.ATL ^
--add Microsoft.VisualStudio.Component.VC.CMake.Project ^
--add Microsoft.VisualStudio.Component.VC.Tools.x86.x64 ^
--add Microsoft.VisualStudio.Component.Windows10SDK ^
--add Microsoft.VisualStudio.Component.Windows10SDK.17763
del /q vs_community.exe
If you prefer you can install everything by hand, but make sure to include "Programming Languages|Visual C++" and "Windows and Web Development|Universal Windows App Development|Windows SDK" in your installation. The components listed above are required.
The following link helps in finding the component name given its ID for Visual Studio 2019.
The command above already installs Python 3. Alternatively, in the Visual Studio installation program, under Individual Components, install Python 3 64 bits (3.7.x).
If you are building a debug version of Swift, you should also install the Python debug binaries.
- In the Windows settings, go to Add and Remove Programs
- Select the Python 3.7.x (64-bit) entry
- Click Modify, then Yes, then Modify again and then Next
- Select Download debug binaries (requires VS 2015 or later)
- Click Install
From the settings application, go to Update & Security
. In the For developers
tab, select Developer Mode
for Use Developer Features
. This is required to enable the creation of symbolic links.
- Clone
swift/main
branch ofapple/llvm-project
into the build workspace - Clone
apple/swift-cmark
,apple/swift
,apple/swift-corelibs-libdispatch
,apple/swift-corelibs-foundation
,apple/swift-corelibs-xctest
,apple/swift-tools-support-core
,apple/swift-llbuild
,apple/swift-argument-parser
,apple/swift-driver
,swiftlang/swift-package-manager
,JPSim/Yams
,swiftlang/indexstore-db
into the build workspace
- Currently, other repositories in the Swift project have not been tested and may not be supported.
This guide assumes your sources live at the root of S:
. If your sources live elsewhere, you can create a substitution for this:
subst S: <path to sources>
S:
git clone https://github.com/apple/llvm-project --branch swift/main llvm-project
git clone -c core.autocrlf=input -c core.symlinks=true https://github.com/apple/swift swift
git clone https://github.com/apple/swift-cmark cmark
git clone https://github.com/apple/swift-corelibs-libdispatch swift-corelibs-libdispatch
git clone https://github.com/apple/swift-corelibs-foundation swift-corelibs-foundation
git clone https://github.com/apple/swift-corelibs-xctest swift-corelibs-xctest
git clone https://github.com/apple/swift-tools-support-core swift-tools-support-core
git clone -c core.symlinks=true https://github.com/apple/swift-llbuild swift-llbuild
git clone https://github.com/JPSim/Yams Yams
git clone https://github.com/apple/swift-driver swift-driver
git clone https://github.com/apple/swift-argument-parser swift-argument-parser
git clone -c core.autocrlf=input https://github.com/swiftlang/swift-package-manager swift-package-manager
git clone https://github.com/swiftlang/indexstore-db indexstore-db
The instructions assume that the dependencies are in S:/Library
. The directory
structure should resemble:
/Library
┝ icu-67
│ ┕ usr/...
├ libcurl-development
│ ┕ usr/...
├ libxml2-development
│ ┕ usr/...
├ sqlite-3.28.0
│ ┕ usr/...
┕ zlib-1.2.11
┕ usr/...
Note that ICU is only required for building Foundation, and SQLite is only needed for building llbuild and onwards. The ICU project provides binaries, alternatively, see the ICU project for details on building ICU from source.
Set up the ucrt
, visualc
, and WinSDK
modules by:
- copying
ucrt.modulemap
located atswift/stdlib/public/Platform/ucrt.modulemap
into${UniversalCRTSdkDir}/Include/${UCRTVersion}/ucrt
asmodule.modulemap
- copying
vcruntime.modulemap
located atswift/stdlib/public/Platform/vcruntime.modulemap
into${VCToolsInstallDir}/include
asmodule.modulemap
- copying
winsdk.modulemap
located atswift/stdlib/public/Platform/winsdk.modulemap
into${UniversalCRTSdkDir}/Include/${UCRTVersion}/um
- and setup the
vcruntime.apinotes
located atswift/stdlib/public/Platform/vcruntime.apinotes
into${VCToolsInstallDir}/include
asvcruntime.apinotes
mklink "%UniversalCRTSdkDir%\Include\%UCRTVersion%\ucrt\module.modulemap" S:\swift\stdlib\public\Platform\ucrt.modulemap
mklink "%UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap" S:\swift\stdlib\public\Platform\winsdk.modulemap
mklink "%VCToolsInstallDir%\include\module.modulemap" S:\swift\stdlib\public\Platform\vcruntime.modulemap
mklink "%VCToolsInstallDir%\include\vcruntime.apinotes" S:\swift\stdlib\public\Platform\vcruntime.apinotes
Warning: Creating the above links usually requires administrator privileges. The quick and easy way to do this is to open a second developer prompt by right clicking whatever shortcut you used to open the first one, choosing Run As Administrator, and pasting the above commands into the resulting window. You can then close the privileged prompt; this is the only step which requires elevation.
cmake -B "S:\b\1" ^
-C S:\swift\cmake\caches\Windows-x86_64.cmake ^
-D CMAKE_BUILD_TYPE=Release ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_C_COMPILER=cl ^
-D CMAKE_C_FLAGS="/GS- /Oy /Gw /Gy" ^
-D CMAKE_CXX_COMPILER=cl ^
-D CMAKE_CXX_FLAGS="/GS- /Oy /Gw /Gy" ^
-D CMAKE_EXE_LINKER_FLAGS="/INCREMENTAL:NO" ^
-D CMAKE_MT=mt ^
-D CMAKE_SHARED_LINKER_FLAGS="/INCREMENTAL:NO" ^
-D LLVM_DEFAULT_TARGET_TRIPLE=x86_64-unknown-windows-msvc ^
-D LLVM_ENABLE_PDB=YES ^
-D LLVM_EXTERNAL_CMARK_SOURCE_DIR=S:\cmark ^
-D LLVM_EXTERNAL_SWIFT_SOURCE_DIR=S:\swift ^
-D SWIFT_PATH_TO_LIBDISPATCH_SOURCE=S:\swift-corelibs-libdispatch ^
-G Ninja ^
-S S:\llvm-project\llvm
ninja -C S:\b\1
NOTE: Linking with debug information (
-D LLVM_ENABLE_PDB=YES
) is very memory intensive. When building with parallel jobs, it is possible to consume upwards of 32 GiB of RAM. You can append-D LLVM_PARALLEL_LINK_JOBS=N -D DLLVM_PARALLEL_LINK_JOBS=N
to reduce the number of parallel link operations toN
which should help reduce the memory pressure. You may need to set this to a low number (e.g. 1) if you see build failures due to memory exhaustion.
path S:\Library\icu-67\usr\bin;S:\b\1\bin;S:\b\1\tools\swift\libdispatch-windows-x86_64-prefix\bin;%PATH%;%ProgramFiles%\Git\usr\bin
ninja -C S:\b\1 check-swift
cmake -B S:\b\2 ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_C_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_CXX_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D ENABLE_SWIFT=YES ^
-G Ninja ^
-S S:\swift-corelibs-libdispatch
ninja -C S:\b\2
ninja -C S:\b\2 check
cmake -B S:\b\3 ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_C_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D CURL_LIBRARY="S:/Library/libcurl-development/usr/lib/libcurl.lib" ^
-D CURL_INCLUDE_DIR="S:/Library/libcurl-development/usr/include" ^
-D ICU_I18N_LIBRARY_RELEASE=S:\library\icu-67\usr\lib\icuin67.lib ^
-D ICU_ROOT=S:\Library\icu-67\usr ^
-D ICU_UC_LIBRARY_RELEASE=S:\Library\icu-67\usr\lib\icuuc67.lib ^
-D LIBXML2_DEFINITIONS="/DLIBXML_STATIC" ^
-D LIBXML2_LIBRARY=S:\Library\libxml2-development\usr\lib\libxml2s.lib ^
-D LIBXML2_INCLUDE_DIR=S:\Library\libxml2-development\usr\include\libxml2 ^
-D ENABLE_TESTING=NO ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-G Ninja ^
-S S:\swift-corelibs-foundation
ninja -C S:\b\3
- Add Foundation to your path:
path S:\b\3\bin;%PATH%
cmake -B S:\b\4 ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D LIT_COMMAND=S:\llvm-project\llvm\utils\lit\lit.py ^
-G Ninja ^
-S S:\swift-corelibs-xctest
ninja -C S:\b\4
- Add XCTest to your path:
path S:\b\4;%PATH%
ninja -C S:\b\4 check-xctest
cmake -B S:\b\3 ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_C_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D CURL_LIBRARY="S:/Library/libcurl-development/usr/lib/libcurl.lib" ^
-D CURL_INCLUDE_DIR="S:/Library/libcurl-development/usr/include" ^
-D ICU_I18N_LIBRARY_RELEASE=S:\library\icu-67\usr\lib\icuin67.lib ^
-D ICU_ROOT=S:\Library\icu-67\usr ^
-D ICU_UC_LIBRARY_RELEASE=S:\Library\icu-67\usr\lib\icuuc67.lib ^
-D LIBXML2_LIBRARY=S:\Library\libxml2-development\usr\lib\libxml2s.lib ^
-D LIBXML2_INCLUDE_DIR=S:\Library\libxml2-development\usr\include\libxml2 ^
-D LIBXML2_DEFINITIONS="/DLIBXML_STATIC" ^
-D ENABLE_TESTING=YES ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D XCTest_DIR=S:\b\4\cmake\modules ^
-G Ninja ^
-S S:\swift-corelibs-foundation
ninja -C S:\b\3
ninja -C S:\b\3 test
cmake -B S:\b\5 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_C_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D SQLite3_INCLUDE_DIR=S:\Library\sqlite-3.28.0\usr\include ^
-D SQLite3_LIBRARY=S:\Library\sqlite-3.28.0\usr\lib\SQLite3.lib ^
-G Ninja ^
-S S:\swift-tools-support-core
ninja -C S:\b\5
cmake -B S:\b\6 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=RelWithDebInfo ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_CXX_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_CXX_FLAGS="-Xclang -fno-split-cold-code" ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D LLBUILD_SUPPORT_BINDINGS=Swift ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D SQLite3_INCLUDE_DIR=S:\Library\sqlite-3.28.0\usr\include ^
-D SQLite3_LIBRARY=S:\Library\sqlite-3.28.0\usr\lib\sqlite3.lib ^
-G Ninja ^
-S S:\swift-llbuild
ninja -C S:\b\6
- Add llbuild to your path:
path S:\b\6\bin;%PATH%
cmake -B S:\b\7 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=Release ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D XCTest_DIR=S:\b\4\cmake\modules ^
-G Ninja ^
-S S:\Yams
ninja -C S:\b\7
cmake -B S:\b\8 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=Release ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D XCTest_DIR=S:\b\4\cmake\modules ^
-G Ninja ^
-S S:\swift-argument-parser
ninja -C S:\b\8
cmake -B S:\b\9 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=Release ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D TSC_DIR=S:\b\5\cmake\modules ^
-D LLBuild_DIR=S:\b\6\cmake\modules ^
-D Yams_DIR=S:\b\7\cmake\modules ^
-D ArgumentParser_DIR=S:\b\8\cmake\modules ^
-G Ninja ^
-S S:\swift-driver
ninja -C S:\b\9
cmake -B S:\b\10 ^
-D BUILD_SHARED_LIBS=YES ^
-D CMAKE_BUILD_TYPE=Release ^
-D CMAKE_C_COMPILER=S:/b/1/bin/clang-cl.exe ^
-D CMAKE_INSTALL_PREFIX=C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr ^
-D CMAKE_MT=mt ^
-D CMAKE_Swift_COMPILER=S:/b/1/bin/swiftc.exe ^
-D dispatch_DIR=S:\b\2\cmake\modules ^
-D Foundation_DIR=S:\b\3\cmake\modules ^
-D TSC_DIR=S:\b\5\cmake\modules ^
-D LLBuild_DIR=S:\b\6\cmake\modules ^
-D Yams_DIR=S:\b\7\cmake\modules ^
-D ArgumentParser_DIR=S:\b\8\cmake\modules ^
-D SwiftDriver_DIR=S:\b\9\cmake\modules ^
-G Ninja ^
-S S:\swift-package-manager
ninja -C S:\b\10
Indicate to swift-package-manager where to find the Package Description before installation:
set SWIFTPM_PD_LIBS=S:\b\10\pm
- Run ninja install:
ninja -C S:\b\1 install
- Add the Swift on Windows binaries path (
C:\Library\Developer\Toolchains\unknown-Asserts-development.xctoolchain\usr\bin
) to thePATH
environment variable.