OSXCross branches:

master:

• Uses cctools 986 and ld64 711. Known to be stable and well-working.

2.0-llvm-based:

• OSXCross based on LLVM tools.
  Easiest to build and recommended for new projects.
  Does not support building for i386.

testing:

• Uses the latest versions of cctools and ld64 — currently cctools 1024.3 and ld64 955.13.
  Takes the longest to build due to additional dependencies introduced in the latest versions.

ppc-test:

• An older branch with support for PPC targets.

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What is OSXCross

OSXCross provides a macOS cross-compilation toolchain.

Supported OSes and architectures

• Host OSes: Linux, *BSD
• Host architectures: x86, x86_64, ARM, AArch64/arm64
• Target architectures: arm64, arm64e, x86_64, i386

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How It Works

macOS cross-compilation requires:

• Clang/LLVM (cross-compilation supported by default)
• A macOS SDK

This branch of OSXCross uses cctools-port. cctools-port provides toolchain tools such as ar, lipo, otool, and ld64 as linker.

OSXCross provides a set of scripts for preparing the SDK, building cctools-port (along with its dependencies), and compiling the compiler wrapper.

It also includes scripts for optionally building:

• Up-to-date LLVM tools and clang (./build_clang.sh, ./build_apple_clang.sh)
• Vanilla GCC as a cross-compiler for target macOS (./build_gcc.sh
• The "compiler-rt" runtime library (./build_compiler_rt.sh)

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Package Manager

A minimal MacPorts package manager is included. See README.MACPORTS.md.

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Installation

Place your packaged SDK in the tarballs/ directory.

Install the following dependencies:

clang cmake git patch python libssl-dev lzma-dev libxml2-dev xz bzip2 cpio libbz2 zlib1g-dev bash

Optional:

• llvm-dev: For Link Time Optimization support and ld64 -bitcode_bundle support
• uuid-dev: For ld64 -random_uuid support

You can run sudo tools/get_dependencies.sh to get these (and the optional packages) automatically. (outdated)

Build Clang (Optional - if you need an up-to-date version of LLVM/Clang)

./build_clang.sh                           # Builds mainline Clang
./build_apple_clang.sh                     # Builds Apple's Clang
INSTALLPREFIX=/opt/clang ./build_clang.sh  # Custom install path

Build OSXCross

By default, this installs the osxcross toolchain into <current-directory>/target.
To specify a different installation path or run the build unattended,
set the TARGET_DIR and/or UNATTENDED environment variables accordingly.

./build.sh 
[TARGET_DIR=/usr/local/osxcross] [OSX_VERSION_MIN=XX.X] [UNATTENDED=1] ./build.sh

Add <target>/bin to your PATH after installation.

Build GCC (Optional)

./build_gcc.sh
GCC_VERSION=5.2.0 ENABLE_FORTRAN=1 ./build_gcc.sh

Install GCC dependencies:

sudo apt-get install gcc g++ zlib1g-dev libmpc-dev libmpfr-dev libgmp-dev

Notes:

• To enable -Werror=implicit-function-declaration, set OSXCROSS_ENABLE_WERROR_IMPLICIT_FUNCTION_DECLARATION=1
• To disable static linking: OSXCROSS_GCC_NO_STATIC_RUNTIME=1
• *-g++-libc++ uses Clang's libc++ — only use if needed

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Packaging the SDK

Please ensure you have read and understood the Xcode license terms before continuing.

SDKs can be extracted either from the full Xcode or from the Xcode Command Line Tools.

On macOS

From Full Xcode

1. Download Xcode
2. Mount Xcode.dmg (Right-click → Open With → DiskImageMounter)
   • If you see a crossed-circle dialog when mounting, ignore it — installation of Xcode is not required
3. Run: ./tools/gen_sdk_package.sh (from the OSXCross package)
4. Copy the resulting SDK (*.tar.* or *.pkg) to a USB stick
5. On Linux/BSD, move the SDK to the tarballs/ directory of OSXCross

From Command Line Tools

1. Download Command Line Tools
2. Mount the Command_Line_Tools_for_Xcode.dmg (Open With → DiskImageMounter)
3. Install Command Line Tools.pkg (Open With → Installer)
4. Run: ./tools/gen_sdk_package_tools.sh
5. Copy the resulting SDK (*.tar.* or *.pkg) to a USB stick
6. On Linux/BSD, move the SDK to the tarballs/ directory of OSXCross

On Linux (and others)

Method 1 (Xcode > 8.0)\ Requires up to 45 GB free disk space. SSD strongly recommended.

1. Download Xcode as described above
2. Install: clang, make, libssl-devel, lzma-devel, and libxml2-devel
3. Run: ./tools/gen_sdk_package_pbzx.sh <xcode>.xip
4. Move the SDK to the tarballs/ directory

Method 2 (up to Xcode 7.3)

1. Download Xcode as described above
2. Install: cmake, libxml2-dev, and fuse
3. Run: ./tools/gen_sdk_package_darling_dmg.sh <xcode>.dmg
4. Move the SDK to the tarballs/ directory

Method 3 (up to Xcode 7.2)

1. Download Xcode as described above
2. Ensure clang and make are installed
3. Run: ./tools/gen_sdk_package_p7zip.sh <xcode>.dmg
4. Move the SDK to the tarballs/ directory

Method 4 (Xcode 4.2)

1. Download Xcode 4.2 for Snow Leopard (ensure it's the correct version)
2. Install dmg2img
3. As root, run: ./tools/mount_xcode_image.sh /path/to/xcode.dmg
4. Follow the on-screen instructions from the script
5. Move the SDK to the tarballs/ directory

From Xcode Command Line Tools

1. Download Command Line Tools as described above
2. Install: clang, make, libssl-devel, lzma-devel, and libxml2-devel
3. Run: ./tools/gen_sdk_package_tools_dmg.sh <command_line_tools_for_xcode>.dmg
4. Move the SDK to the tarballs/ directory

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Usage Examples

Compile test.cpp

• i386: i386-apple-darwinXX-clang++ test.cpp -O3 -o test (if your SDK supports i386)
• x86_64: x86_64-apple-darwinXX-clang++ test.cpp -O3 -o test
• arm64: arm64-apple-darwinXX-clang++ test.cpp -O3 -o test
• arm64e: arm64e-apple-darwinXX-clang++ test.cpp -O3 -o test

Or by using xcrun:

• i386: xcrun clang++ -arch x86_64 test.cpp -O3 -o test
• x86_64: xcrun clang++ -arch x86_64 test.cpp -O3 -o test
• arm64: xcrun clang++ -arch arm64 test.cpp -O3 -o test
• arm64e: xcrun clang++ -arch arm64e test.cpp -O3 -o test

GCC: Replace clang++ with g++ as needed

Check your target version with osxcross-conf, see TARGET.

Build Makefile project

xcrun -f clang prints the path to clang.

make CC=$(xcrun -f clang) CXX=$(xcrun -f clang++)

Build autotools project

CC=x86_64-apple-darwinXX-clang CXX=x86_64-apple-darwinXX-clang++ ./configure --host=x86_64-apple-darwinXX

libc++ Example (macOS 10.7+ required)

xcrun clang++ -stdlib=libc++ -std=c++11 test.cpp -o test

Shortcut:

x86_64-apple-darwinXX-clang++-libc++ -std=c++11 test.cpp -o test

LTO Example

xcrun clang++ test1.cpp -O3 -flto -c
xcrun clang++ test2.cpp -O3 -flto -c
xcrun clang++ -O3 -flto test1.o test2.o -o test

Universal Binary

xcrun clang++ test.cpp -O3 -arch x86_64 -arch arm64 -o test

GCC:

xcrun g++ -arch x86_64 test.cpp -O3 -o test.x86_64
xcrun g++ -arch arm64 test.cpp -O3 -o test.arm64
xcrun lipo -create test.x86_64 test.arm64 -output test

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Deployment Target

Default:

• SDK ≤ 10.13 → macOS 10.6
• SDK ≥ 10.14 → macOS 10.9
• SDK ≥ 14.0 → macOS 10.13

Can be overriden via:

1. During the build: OSX_VERSION_MIN=XX.X ./build.sh.
2. By passing -mmacos-version-min=XX.X to the compiler.
3. By setting MACOSX_DEPLOYMENT_TARGET=XX.X env var.

Note: Deployment target ≥ 10.9 defaults to libc++.
Can be explicitely overriden by setting the C++ library to libstdc++ via -stdlib=libstdc++.

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Projects Using OSXCross

• multiarch/crossbuild:
  various cross-compilers
  (Systems: Linux, macOS, Windows, Archs: x86_64,i386, arm, ppc, mips)
  in Docker. OSXCross powers the Darwin builds.
• Smartmontools

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License

• scripts/wrapper: GPLv2
• cctools/ld64: APSL 2.0 (legacy)
• xar: New BSD