LuaJIT

# Installation

LuaJIT is only distributed as a source package. This page explains how to build and install LuaJIT with different operating systems and C compilers.

For the impatient (on POSIX systems):

    make && sudo make install

LuaJIT currently builds out-of-the box on most systems. Here's the compatibility matrix for the supported combinations of operating systems, CPUs and compilers:

CPU / OS | Linux or Android | *BSD, Other | OSX 10.4+ or iOS 3.0+ | Windows XP/Vista/7
x86 (32 bit) | GCC 4.x GCC 3.4 | GCC 4.x GCC 3.4 | GCC 4.x GCC 3.4 | MSVC, MSVC/EE WinSDK MinGW, Cygwin
x64 (64 bit) | GCC 4.x |  | GCC 4.x | MSVC + SDK v7.0 WinSDK v7.0
ARMv5+ ARM9E+ | GCC 4.2+ | GCC 4.2+ | GCC 4.2+ |
PPC | GCC 4.3+ | GCC 4.3+ GCC 4.1 (PS3) |  | XEDK (Xbox 360)
PPC/e500v2 | GCC 4.3+ | GCC 4.3+ |  |
MIPS | GCC 4.3+ | GCC 4.3+ |  |

## Configuring LuaJIT

The standard configuration should work fine for most installations. Usually there is no need to tweak the settings. The following files hold all user-configurable settings:

- `src/luaconf.h` sets some configuration variables.
- `Makefile` has settings for installing LuaJIT (POSIX only).
- `src/Makefile` has settings for compiling LuaJIT under POSIX, MinGW or Cygwin.
- `src/msvcbuild.bat` has settings for compiling LuaJIT with MSVC or WinSDK.

Please read the instructions given in these files, before changing any settings.

## POSIX Systems (Linux, OSX, *BSD etc.)

### Prerequisites

Depending on your distribution, you may need to install a package for GCC, the development headers and/or a complete SDK. E.g. on a current Debian/Ubuntu, install `libc6-dev` with the package manager.

Download the current source package of LuaJIT (pick the .tar.gz), if you haven't already done so. Move it to a directory of your choice, open a terminal window and change to this directory. Now unpack the archive and change to the newly created directory:

    tar zxf LuaJIT-2.0.2.tar.gz
    cd LuaJIT-2.0.2

### Building LuaJIT

The supplied Makefiles try to auto-detect the settings needed for your operating system and your compiler. They need to be run with GNU Make, which is probably the default on your system, anyway. Simply run:

    make

This always builds a native x86, x64 or PPC binary, depending on the host OS you're running this command on. Check the section on cross-compilation for more options.

By default, modules are only searched under the prefix `/usr/local`. You can add an extra prefix to the search paths by appending the `PREFIX` option, e.g.:

    make PREFIX=/home/myself/lj2

Note for OSX: if the `MACOSX_DEPLOYMENT_TARGET` environment variable is not set, then it's forced to `10.4`.

### Installing LuaJIT

The top-level Makefile installs LuaJIT by default under `/usr/local`, i.e. the executable ends up in `/usr/local/bin` and so on. You need root privileges to write to this path. So, assuming sudo is installed on your system, run the following command and enter your sudo password:

    sudo make install

Otherwise specify the directory prefix as an absolute path, e.g.:

    make install PREFIX=/home/myself/lj2

Obviously the prefixes given during build and installation need to be the same.

## Windows Systems

### Prerequisites

Either install one of the open source SDKs (» MinGW or » Cygwin), which come with a modified GCC plus the required development headers.

Or install Microsoft's Visual C++ (MSVC). The freely downloadable » Express Edition works just fine, but only contains an x86 compiler.

The freely downloadable » Windows SDK only comes with command line tools, but this is all you need to build LuaJIT. It contains x86 and x64 compilers.

Next, download the source package and unpack it using an archive manager (e.g. the Windows Explorer) to a directory of your choice.

### Building with MSVC

Open a "Visual Studio .NET Command Prompt", `cd` to the directory where you've unpacked the sources and run these commands:

    cd src
    msvcbuild

Then follow the installation instructions below.

### Building with the Windows SDK

Open a "Windows SDK Command Shell" and select the x86 compiler:

    setenv /release /x86

Or select the x64 compiler:

    setenv /release /x64

Then `cd` to the directory where you've unpacked the sources and run these commands:

    cd src
    msvcbuild

Then follow the installation instructions below.

### Building with MinGW or Cygwin

Open a command prompt window and make sure the MinGW or Cygwin programs are in your path. Then `cd` to the directory where you've unpacked the sources and run this command for MinGW:

    mingw32-make

Or this command for Cygwin:

    make

Then follow the installation instructions below.

### Installing LuaJIT

Copy `luajit.exe` and `lua51.dll` (built in the `src` directory) to a newly created directory (any location is ok). Add `lua` and `lua\jit` directories below it and copy all Lua files from the `src\jit` directory of the distribution to the latter directory.

There are no hardcoded absolute path names — all modules are loaded relative to the directory where `luajit.exe` is installed (see `src/luaconf.h`).

## Cross-compiling LuaJIT

The GNU Makefile-based build system allows cross-compiling on any host for any supported target, as long as both architectures have the same pointer size. If you want to cross-compile to any 32 bit target on an x64 OS, you need to install the multilib development package (e.g. `libc6-dev-i386` on Debian/Ubuntu) and build a 32 bit host part (`HOST_CC="gcc -m32"`).

You need to specify `TARGET_SYS` whenever the host OS and the target OS differ, or you'll get assembler or linker errors. E.g. if you're compiling on a Windows or OSX host for embedded Linux or Android, you need to add `TARGET_SYS=Linux` to the examples below. For a minimal target OS, you may need to disable the built-in allocator in `src/Makefile` and use `TARGET_SYS=Other`. The examples below only show some popular targets — please check the comments in `src/Makefile` for more details.

    # Cross-compile to a 32 bit binary on a multilib x64 OS
    make CC="gcc -m32"

    # Cross-compile on Debian/Ubuntu for Windows (mingw32 package)
    make HOST_CC="gcc -m32" CROSS=i586-mingw32msvc- TARGET_SYS=Windows

The `CROSS` prefix allows specifying a standard GNU cross-compile toolchain (Binutils, GCC and a matching libc). The prefix may vary depending on the `--target` the toolchain was built for (note the `CROSS` prefix has a trailing `"-"`). The examples below use the canonical toolchain triplets for Linux.

Since there's often no easy way to detect CPU features at runtime, it's important to compile with the proper CPU or architecture settings. You can specify these when building the toolchain yourself. Or add `-mcpu=...` or `-march=...` to `TARGET_CFLAGS`. For ARM it's important to have the correct `-mfloat-abi=...` setting, too. Otherwise LuaJIT may not run at the full performance of your target CPU.

    # ARM soft-float
    make HOST_CC="gcc -m32" CROSS=arm-linux-gnueabi- \
         TARGET_CFLAGS="-mfloat-abi=soft"

    # ARM soft-float ABI with VFP (example for Cortex-A8)
    make HOST_CC="gcc -m32" CROSS=arm-linux-gnueabi- \
         TARGET_CFLAGS="-mcpu=cortex-a8 -mfloat-abi=softfp"

    # ARM hard-float ABI with VFP (armhf, requires recent toolchain)
    make HOST_CC="gcc -m32" CROSS=arm-linux-gnueabihf-

    # PPC
    make HOST_CC="gcc -m32" CROSS=powerpc-linux-gnu-
    # PPC/e500v2 (fast interpreter only)
    make HOST_CC="gcc -m32" CROSS=powerpc-e500v2-linux-gnuspe-

    # MIPS big-endian
    make HOST_CC="gcc -m32" CROSS=mips-linux-
    # MIPS little-endian
    make HOST_CC="gcc -m32" CROSS=mipsel-linux-

You can cross-compile for Android using the » Android NDK. The environment variables need to match the install locations and the desired target platform. E.g. Android 4.0 corresponds to ABI level 14. For details check the folder `docs` in the NDK directory.

Only a few common variations for the different CPUs, ABIs and platforms are listed. Please use your own judgement for which combination you want to build/deploy or which lowest common denominator you want to pick:

    # Android/ARM, armeabi (ARMv5TE soft-float), Android 2.2+ (Froyo)
    NDK=/opt/android/ndk
    NDKABI=8
    NDKVER=$NDK/toolchains/arm-linux-androideabi-4.6
    NDKP=$NDKVER/prebuilt/linux-x86/bin/arm-linux-androideabi-
    NDKF="--sysroot $NDK/platforms/android-$NDKABI/arch-arm"
    make HOST_CC="gcc -m32" CROSS=$NDKP TARGET_FLAGS="$NDKF"

    # Android/ARM, armeabi-v7a (ARMv7 VFP), Android 4.0+ (ICS)
    NDK=/opt/android/ndk
    NDKABI=14
    NDKVER=$NDK/toolchains/arm-linux-androideabi-4.6
    NDKP=$NDKVER/prebuilt/linux-x86/bin/arm-linux-androideabi-
    NDKF="--sysroot $NDK/platforms/android-$NDKABI/arch-arm"
    NDKARCH="-march=armv7-a -mfloat-abi=softfp -Wl,--fix-cortex-a8"
    make HOST_CC="gcc -m32" CROSS=$NDKP TARGET_FLAGS="$NDKF $NDKARCH"

    # Android/MIPS, mips (MIPS32R1 hard-float), Android 4.0+ (ICS)
    NDK=/opt/android/ndk
    NDKABI=14
    NDKVER=$NDK/toolchains/mipsel-linux-android-4.6
    NDKP=$NDKVER/prebuilt/linux-x86/bin/mipsel-linux-android-
    NDKF="--sysroot $NDK/platforms/android-$NDKABI/arch-mips"
    make HOST_CC="gcc -m32" CROSS=$NDKP TARGET_FLAGS="$NDKF"

    # Android/x86, x86 (i686 SSE3), Android 4.0+ (ICS)
    NDK=/opt/android/ndk
    NDKABI=14
    NDKVER=$NDK/toolchains/x86-4.6
    NDKP=$NDKVER/prebuilt/linux-x86/bin/i686-linux-android-
    NDKF="--sysroot $NDK/platforms/android-$NDKABI/arch-x86"
    make HOST_CC="gcc -m32" CROSS=$NDKP TARGET_FLAGS="$NDKF"

You can cross-compile for iOS 3.0+ (iPhone/iPad) using the » iOS SDK. The environment variables need to match the iOS SDK version:

Note: the JIT compiler is disabled for iOS, because regular iOS Apps are not allowed to generate code at runtime. You'll only get the performance of the LuaJIT interpreter on iOS. This is still faster than plain Lua, but much slower than the JIT compiler. Please complain to Apple, not me. Or use Android. :-p

    IXCODE=`xcode-select -print-path`
    ISDK=$IXCODE/Platforms/iPhoneOS.platform/Developer
    ISDKVER=iPhoneOS6.0.sdk
    ISDKP=$ISDK/usr/bin/
    ISDKF="-arch armv7 -isysroot $ISDK/SDKs/$ISDKVER"
    make HOST_CC="gcc -m32 -arch i386" CROSS=$ISDKP TARGET_FLAGS="$ISDKF" \
         TARGET_SYS=iOS

You can cross-compile for PS3 using the PS3 SDK from a Linux host or a Windows host (requires 32 bit MinGW (GCC) on the host, too). Due to restrictions on consoles, the JIT compiler is disabled and only the fast interpreter is built:

    make HOST_CC="gcc -m32" CROSS=ppu-lv2-

You can cross-compile for Xbox 360 using the Xbox 360 SDK (MSVC + XEDK). Due to restrictions on consoles, the JIT compiler is disabled and only the fast interpreter is built.

Open a "Visual Studio .NET Command Prompt" (32 bit host compiler), `cd` to the directory where you've unpacked the sources and run the following commands. This builds a static library `luajit20.lib`, which can be linked against your game, just like the Lua library.

    cd src
    xedkbuild

## Embedding LuaJIT

LuaJIT is API-compatible with Lua 5.1. If you've already embedded Lua into your application, you probably don't need to do anything to switch to LuaJIT, except link with a different library:

- It's strongly suggested to build LuaJIT separately using the supplied build system. Please do not attempt to integrate the individual source files into your build tree. You'll most likely get the internal build dependencies wrong or mess up the compiler flags. Treat LuaJIT like any other external library and link your application with either the dynamic or static library, depending on your needs.
- If you want to load C modules compiled for plain Lua with `require()`, you need to make sure the public symbols (e.g. `lua_pushnumber`) are exported, too:
  - On POSIX systems you can either link to the shared library or link the static library into your application. In the latter case you'll need to export all public symbols from your main executable (e.g. `-Wl,-E` on Linux) and add the external dependencies (e.g. `-lm -ldl` on Linux).
  - Since Windows symbols are bound to a specific DLL name, you need to link to the `lua51.dll` created by the LuaJIT build (do not rename the DLL). You may link LuaJIT statically on Windows only if you don't intend to load Lua/C modules at runtime.
- If you're building a 64 bit application on OSX which links directly or indirectly against LuaJIT, you need to link your main executable with these flags:

      -pagezero_size 10000 -image_base 100000000

  Also, it's recommended to `rebase` all (self-compiled) shared libraries which are loaded at runtime on OSX/x64 (e.g. C extension modules for Lua). See: `man rebase`

Additional hints for initializing LuaJIT using the C API functions:

- Here's a » simple example for embedding Lua or LuaJIT into your application.
- Make sure you use `luaL_newstate`. Avoid using `lua_newstate`, since this uses the (slower) default memory allocator from your system (no support for this on x64).
- Make sure you use `luaL_openlibs` and not the old Lua 5.0 style of calling `luaopen_base` etc. directly.
- To change or extend the list of standard libraries to load, copy `src/lib_init.c` to your project and modify it accordingly. Make sure the `jit` library is loaded or the JIT compiler will not be activated.
- The `bit.*` module for bitwise operations is already built-in. There's no need to statically link » Lua BitOp to your application.

## Hints for Distribution Maintainers

The LuaJIT build system has extra provisions for the needs of most POSIX-based distributions. If you're a package maintainer for a distribution, please make use of these features and avoid patching, subverting, autotoolizing or messing up the build system in unspeakable ways.

There should be absolutely no need to patch `luaconf.h` or any of the Makefiles. And please do not hand-pick files for your packages — simply use whatever `make install` creates. There's a reason for all of the files and directories it creates.

The build system uses GNU make and auto-detects most settings based on the host you're building it on. This should work fine for native builds, even when sandboxed. You may need to pass some of the following flags to both the `make` and the `make install` command lines for a regular distribution build:

- `PREFIX` overrides the installation path and should usually be set to `/usr`. Setting this also changes the module paths and the `-rpath` of the shared library.
- `DESTDIR` is an absolute path which allows you to install to a shadow tree instead of the root tree of the build system.
- Have a look at the top-level `Makefile` and `src/Makefile` for additional variables to tweak. The following variables may be overridden, but it's not recommended, except for special needs like cross-builds: `BUILDMODE, CC, HOST_CC, STATIC_CC, DYNAMIC_CC, CFLAGS, HOST_CFLAGS, TARGET_CFLAGS, LDFLAGS, HOST_LDFLAGS, TARGET_LDFLAGS, TARGET_SHLDFLAGS, TARGET_FLAGS, LIBS, HOST_LIBS, TARGET_LIBS, CROSS, HOST_SYS, TARGET_SYS`

The build system has a special target for an amalgamated build, i.e. `make amalg`. This compiles the LuaJIT core as one huge C file and allows GCC to generate faster and shorter code. Alas, this requires lots of memory during the build. This may be a problem for some users, that's why it's not enabled by default. But it shouldn't be a problem for most build farms. It's recommended that binary distributions use this target for their LuaJIT builds.

The tl;dr version of the above:

    make amalg PREFIX=/usr && \
    make install PREFIX=/usr DESTDIR=/tmp/buildroot

Finally, if you encounter any difficulties, please contact me first, instead of releasing a broken package onto unsuspecting users. Because they'll usually gonna complain to me (the upstream) and not you (the package maintainer), anyway.

Copyright © 2005-2013 Mike Pall · Contact