This document describes how to build Swift for Windows natively. See the Windows doc for more about what is possible with Swift on Windows.
There are two supported ways to build Swift on Windows, they are
clang-cl
clang-cl
is recommended over MSVC for building Swift on Windows. Although it is possible to build the compiler and the standard library with MSVC, and use those built products to compile a Swift program, it won't be possible to run the binary without seperately obtaining the Swift runtime. On the other hand, clang-cl
is able to build the runtime, which makes it possible to build and run all the components required for Swift natively on Windows.
clang-cl
Path
environment variableapple/swift-cmark
into a folder named cmark
apple/swift-clang
into a folder named clang
apple/swift-llvm
into a folder named llvm
apple/swift
into a folder named swift
icu
in the same directory as the other Swift project repositories.src/win32/allinone.sln
in Visual Studio.<icu-source>/bin
folder to your Path
environment variable.VsDevCmd -arch=amd64
If instead you're compiling for a 32-bit Windows target, adapt the arch
argument to x86
and run
VsDevCmd -arch=x86
set swift_source_dir=path-to-directory-containing-all-cloned-repositories
mkdir "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64" pushd "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64" cmake -G "Ninja" "%swift_source_dir%/cmark" popd cmake --build "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64/"
compiler-rt
below, which should give faster build times.mklink /J "%swift_source_dir%/llvm/tools/clang" "%swift_source_dir%/clang" mklink /J "%swift_source_dir%/llvm/tools/compiler-rt" "%swift_source_dir%/compiler-rt" mkdir "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64" pushd "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64" cmake -G "Ninja"^ -DLLVM_ENABLE_ASSERTIONS=TRUE^ -DCMAKE_BUILD_TYPE=RelWithDebInfo^ -DLLVM_TOOL_SWIFT_BUILD=NO^ -DLLVM_INCLUDE_DOCS=TRUE^ -DLLVM_TOOL_COMPILER_RT_BUILD=TRUE^ -DLLVM_BUILD_EXTERNAL_COMPILER_RT=TRUE^ -DLLVM_LIT_ARGS=-sv^ -DLLVM_TARGETS_TO_BUILD=X86^ "%swift_source_dir%/llvm" popd cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/llvm-windows-amd64"
SWIFT_WINDOWS_LIB_DIRECTORY
parameter depending on your target platform or Windows SDK version.clang-cl
is recommended (see the Clang-cl section below).mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja" pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja" cmake -G "Ninja" "%swift_source_dir%/swift"^ -DCMAKE_BUILD_TYPE=Debug^ -DSWIFT_PATH_TO_CMARK_SOURCE="%swift_source_dir%/cmark"^ -DSWIFT_PATH_TO_CMARK_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64"^ -DSWIFT_CMARK_LIBRARY_DIR="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64/src"^ -DSWIFT_PATH_TO_LLVM_SOURCE="%swift_source_dir%/llvm"^ -DSWIFT_PATH_TO_LLVM_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"^ -DSWIFT_PATH_TO_CLANG_SOURCE="%swift_source_dir%/llvm/tools/clang"^ -DSWIFT_PATH_TO_CLANG_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"^ -DICU_UC_INCLUDE_DIRS="%swift_source_dir%/icu/include"^ -DICU_UC_LIBRARY_DIRS="%swift_source_dir%/icu/lib64"^ -DICU_I18N_INCLUDE_DIRS="%swift_source_dir%/icu/include"^ -DICU_I18N_LIBRARY_DIRS="%swift_source_dir%/icu/lib64"^ -DICU_UC_LIB_NAME="icuuc"^ -DICU_I18N_LIB_NAME="icuin"^ -DSWIFT_INCLUDE_DOCS=FALSE^ -DSWIFT_INCLUDE_TESTS=FALSE^ -DCMAKE_C_COMPILER="<path-to-llvm-bin>/clang-cl.exe"^ -DCMAKE_CXX_COMPILER="<path-to-llvm-bin>/bin/clang-cl.exe"^ -DCMAKE_C_FLAGS="-fms-compatibility-version=19.00 /Z7"^ -DCMAKE_CXX_FLAGS="-fms-compatibility-version=19.00 -Z7" ^ -DSWIFT_BUILD_RUNTIME_WITH_HOST_COMPILER=FALSE popd cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
swift
project due to an MSBuild limitation that file paths cannot exceed 260 characters. These can be ignored, as they occur after the build when writing the last build status to a file.cmake -G "Visual Studio 15" "%swift_source_dir%/swift"^ -DCMAKE_GENERATOR_PLATFORM="x64"^ ...
Follow instructions 1-6 for clang-cl
, but run the following instead to build Swift
mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja" pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja" cmake -G "Ninja" "%swift_source_dir%/swift"^ -DCMAKE_BUILD_TYPE=Debug^ -DSWIFT_PATH_TO_CMARK_SOURCE="%swift_source_dir%/cmark"^ -DSWIFT_PATH_TO_CMARK_BUILD="%swift_source_dir%/build/Ninja-DebugAssert/cmark-windows-amd64"^ -DSWIFT_CMARK_LIBRARY_DIR="%swift_source_dir%/build/Ninja-DebugAssert/cmark-windows-amd64/src"^ -DSWIFT_PATH_TO_LLVM_SOURCE="%swift_source_dir%/llvm"^ -DSWIFT_PATH_TO_LLVM_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"^ -DSWIFT_PATH_TO_CLANG_SOURCE="%swift_source_dir%/llvm/tools/clang"^ -DSWIFT_PATH_TO_CLANG_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"^ -DICU_UC_INCLUDE_DIRS="%swift_source_dir%/icu/include"^ -DICU_UC_LIBRARY_DIRS="%swift_source_dir%/icu/lib64"^ -DICU_I18N_INCLUDE_DIRS="%swift_source_dir%/icu/include"^ -DICU_I18N_LIBRARY_DIRS="%swift_source_dir%/icu/lib64"^ -DICU_UC_LIB_NAME="icuuc"^ -DICU_I18N_LIB_NAME="icuin"^ -DSWIFT_INCLUDE_DOCS=FALSE^ -DSWIFT_INCLUDE_TESTS=FALSE^ -DSWIFT_BUILD_DYNAMIC_SDK_OVERLAY=FALSE^ -DSWIFT_BUILD_RUNTIME_WITH_HOST_COMPILER=FALSE popd cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"