Cross compiling Rust for Windows MSVC target

2021/03/14 |

Programming/ Rust

| Programming Rust

Cross compiling Rust for Windows MSVC target

Generally, We can compiling Rust applications for the Windows target x86_64-pc-windows-gnu. But for the Windows target x86_64-pc-windows-msvc, we need Wine or on the Windows host. Now, we can use lld to create the Windows target x86_64-pc-windows-gnu.

Copy MSVC libraries to the Linux host

The target directory

# x86_64-unknown-linux-gnu -> x86_64-pc-windows-msvc
export RUST_MSVC_LIB_PATH=${RUSTUP_HOME:-~/.rustup}/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-pc-windows-msvc/lib

# x86_64-unknown-linux-musl -> x86_64-pc-windows-msvc
export RUST_MSVC_LIB_PATH=${RUSTUP_HOME:-~/.rustup}/toolchains/stable-x86_64-unknown-linux-musl/lib/rustlib/x86_64-pc-windows-msvc/lib

Copy VC runtime libraries

• C runtime (CRT) and C++ Standard Library (STL) files

# You need adjust the source directory if needed.
cd "/mnt/c/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.29.30133/lib/x64"
cd "/mnt/c/Program Files (x86)/Microsoft Visual Studio/2019/BuildTools/VC/Tools/MSVC/14.29.30133/lib/x64"

cp vcruntime.lib                    ${RUST_MSVC_LIB_PATH}/vcruntime.lib
cp msvcrt.lib                       ${RUST_MSVC_LIB_PATH}/msvcrt.lib
cp msvcprt.lib                      ${RUST_MSVC_LIB_PATH}/msvcprt.lib
cp iso_stdio_wide_specifiers.lib    ${RUST_MSVC_LIB_PATH}/iso_stdio_wide_specifiers.lib
cp libvcruntime.lib                 ${RUST_MSVC_LIB_PATH}/libvcruntime.lib
cp libcmt.lib                       ${RUST_MSVC_LIB_PATH}/libcmt.lib
cp libcpmt.lib                      ${RUST_MSVC_LIB_PATH}/libcpmt.lib

Copy UCRT libraries

• C runtime (CRT) and C++ Standard Library (STL) files

# You need adjust the source directory if needed.
cd "/mnt/c/Program Files (x86)/Windows Kits/10/Lib/10.0.19041.0/ucrt/x64"

cp ucrt.lib     ${RUST_MSVC_LIB_PATH}/ucrt.lib
cp libucrt.lib  ${RUST_MSVC_LIB_PATH}/libucrt.lib

Copy Windows API libraries

# You need adjust the source directory if needed.
cd "/mnt/c/Program Files (x86)/Windows Kits/10/Lib/10.0.19041.0/um/x64"

cp AdvAPI32.Lib ${RUST_MSVC_LIB_PATH}/advapi32.lib
cp bcrypt.lib   ${RUST_MSVC_LIB_PATH}/bcrypt.lib
cp Crypt32.Lib  ${RUST_MSVC_LIB_PATH}/crypt32.lib
cp kernel32.Lib ${RUST_MSVC_LIB_PATH}/kernel32.lib
cp MsWSock.Lib  ${RUST_MSVC_LIB_PATH}/mswsock.lib
cp odbc32.lib   ${RUST_MSVC_LIB_PATH}/odbc32.lib
cp OneCore_apiset.Lib ${RUST_MSVC_LIB_PATH}/onecore_apiset.lib
cp OneCore.Lib  ${RUST_MSVC_LIB_PATH}/onecore.lib
cp Psapi.Lib    ${RUST_MSVC_LIB_PATH}/psapi.lib
cp User32.Lib   ${RUST_MSVC_LIB_PATH}/user32.lib
cp UserEnv.Lib  ${RUST_MSVC_LIB_PATH}/userenv.lib
cp Uuid.Lib     ${RUST_MSVC_LIB_PATH}/uuid.lib
cp WS2_32.Lib   ${RUST_MSVC_LIB_PATH}/ws2_32.lib

Windows umbrella libraries

• Windows API sets
• Detect API set availability
• Windows umbrella libraries
• Building for OneCore

Library	Scenario
OneCore.lib	All editions of Windows 7 and later, no UWP support
OneCore_apiset.lib	This library provides the same coverage as OneCore.lib, but uses API set direct forwarding. Note that using this library will be compatible only with the Windows 10 version as specified by the SDK verion you’re targeting, or greater.
OneCoreUAP.lib	Windows 7 and later, UWP editions (Desktop, IoT, HoloLens, but not Nano Server) of Windows 10
OneCoreUAP_apiset.lib	This library provides the same coverage as OneCoreUAP.lib, but uses the API set direct forwarding technique. Note that using this library will be compatible only with the Windows 10 version as specified by the SDK you’re targeting, or greater.

How we known which libraries need to be copy

During the link time, rust will report which libraries not found, just find them on Windows, and copy them to Linux.

Rust linked libraries

• https://github.com/rust-lang/rust/blob/master/library/std/src/sys/windows/mod.rs

#[link(name = "advapi32")]
#[link(name = "ws2_32")]
#[link(name = "userenv")]

LLVM linked libraries

• https://github.com/llvm/llvm-project/blob/main/libcxx/CMakeLists.txt

target_link_libraries(${target} PRIVATE ucrt${LIB_SUFFIX}) # Universal C runtime
target_link_libraries(${target} PRIVATE vcruntime${LIB_SUFFIX}) # C++ runtime
target_link_libraries(${target} PRIVATE msvcrt${LIB_SUFFIX}) # C runtime startup files
target_link_libraries(${target} PRIVATE msvcprt${LIB_SUFFIX}) # C++ standard library. Required for exception_ptr internals.
# Required for standards-complaint wide character formatting functions (e.g. `printfw`/`scanfw`)
target_link_libraries(${target} PRIVATE iso_stdio_wide_specifiers)

Let’s have a test

Hello World

$ cat << EOF > hello-world.rs
fn main() {
    println!("Hello, world!");
}
EOF

Use DLL C runtime library

$ rustc -C opt-level=3 -C link-arg="-s" \
    --target=x86_64-pc-windows-msvc -C linker=lld-link -o hello-world-windows-x86_64.exe \
    hello-world.rs

$ du -ks hello-world-windows-x86_64.exe
152     hello-world-windows-x86_64.exe

$ file hello-world-windows-x86_64.exe
hello-world-windows-x86_64.exe: PE32+ executable (console) x86-64, for MS Windows

$ /usr/bin/x86_64-w64-mingw32-objdump -x hello-world-windows-x86_64.exe | grep -E '^\s*DLL Name'
        DLL Name: KERNEL32.dll
        DLL Name: VCRUNTIME140.dll
        DLL Name: api-ms-win-crt-runtime-l1-1-0.dll
        DLL Name: api-ms-win-crt-stdio-l1-1-0.dll
        DLL Name: api-ms-win-crt-math-l1-1-0.dll
        DLL Name: api-ms-win-crt-locale-l1-1-0.dll
        DLL Name: api-ms-win-crt-heap-l1-1-0.dll

PS C:\> dumpbin /NOLOGO /DEPENDENTS hello-world-windows-x86_64.exe

Dump of file hello-world-windows-x86_64.exe

File Type: EXECUTABLE IMAGE

  Image has the following dependencies:

    KERNEL32.dll
    VCRUNTIME140.dll
    api-ms-win-crt-runtime-l1-1-0.dll
    api-ms-win-crt-stdio-l1-1-0.dll
    api-ms-win-crt-math-l1-1-0.dll
    api-ms-win-crt-locale-l1-1-0.dll
    api-ms-win-crt-heap-l1-1-0.dll

  Summary

        1000 .00cfg
        1000 .data
        1000 .gehcont
        2000 .pdata
        8000 .rdata
        1000 .reloc
       1C000 .text
        1000 .tls

Use static C runtime library

$ rustc -C opt-level=3 -C link-arg="-s" -C "target-feature=+crt-static" \
    --target=x86_64-pc-windows-msvc -C linker=lld-link -o hello-world-windows-x86_64.exe \
    hello-world.rs

$ du -ks hello-world-windows-x86_64.exe
244     hello-world-windows-x86_64.exe

$ file hello-world-windows-x86_64.exe
hello-world-windows-x86_64.exe: PE32+ executable (console) x86-64, for MS Windows

$ /usr/bin/x86_64-w64-mingw32-objdump -x hello-world-windows-x86_64.exe | grep -E '^\s*DLL Name'
        DLL Name: KERNEL32.dll

PS C:\> dumpbin /NOLOGO /DEPENDENTS hello-world-windows-x86_64.exe

Dump of file hello-world-windows-x86_64.exe

File Type: EXECUTABLE IMAGE

  Image has the following dependencies:

    KERNEL32.dll

  Summary

        1000 .00cfg
        2000 .data
        1000 .gehcont
        3000 .pdata
       10000 .rdata
        1000 .reloc
       29000 .text
        1000 .tls
        1000 _RDATA