MLton is a whole-program optimizing compiler for the Standard ML programming language.

• Portability. Runs on the following platforms:

  • ARM: Linux (Debian).
  • Alpha: Linux (Debian).
  • AMD64: Darwin (Mac OS X), FreeBSD, Linux (Debian, Fedora, ...), Solaris (10 and above).
  • HPPA: HPUX (11.11 and above), Linux (Debian).
  • IA64: HPUX (11.11 and above), Linux (Debian).
  • PowerPC: AIX (5.2 and above), Darwin (Mac OS X), Linux (Debian, Fedora).
  • PowerPC64: AIX (5.2 and above).
  • S390: Linux (Debian).
  • Sparc: Linux (Debian), Solaris (8 and above).
  • X86: Cygwin/Windows, Darwin (Mac OS X), FreeBSD, Linux (Debian, Fedora, ...), MinGW/Windows, NetBSD, OpenBSD, Solaris (10 and above).

• Robustness.

  • Supports the full SML 97 language as given in The Definition of Standard ML (Revised).
  • A complete implementation of the Basis Library.
  • Generates standalone executables.
  • Compiles large programs.
  • Support for large amounts of memory (up to 4G on 32-bit systems; more on 64-bit systems).
  • Support for large array lengths (up to 2^31 - 1 on 32-bit systems; up to 2^63-1 on 64-bit systems).
  • Support for large files, using 64-bit file positions.

• Performance.

  • Executables have excellent running times.
  • Generates small executables.
  • Untagged and unboxed native integers, reals, and words.
  • Unboxed native arrays.
  • Multiple garbage collection strategies.
  • Fast arbitrary-precision arithmetic based on the GnuMP.

• Tools.

  • Source-level profiling for both time and allocation.
  • MLLex lexer generator.
  • MLYacc parser generator.
  • ML-NLFFIGEN foreign-function-interface generator.

• Extensions.

  • A simple and fast C FFI that supports calling from SML to C and from C to SML.
  • The ML Basis system for programming in the very large.
  • Libraries for continuations, finalization, interval timers, random numbers, resource limits, resource usage, signal handlers, object size, system logging, threads, weak pointers, and world save and restore.

• GCC 4.1.x or later
• GNU Multiple Precision Library. Check if GMP is already present on your system (whereis gmp libgmp), typically on GCC search path (gcc -v -x c -E -).
• MLton (recommended) or some other SML compiler to bootstrap. The easiest way is to install a pre-built binary package for MLton using your package manager. If using SML/NJ, see Compiling with SML/NJ.

MLton can be built from source using the usual ./configure && make && make install sequence to install under the system default installation directory (typically, /usr/local). Optionally, you can specify the --prefix argument to install MLton into a custom directory.

You can instruct MLton to look for gmp.h outside your include path or for libgmp outside your library search path using --with-gmp-lib and --with-gmp-include configure options, as in:

gzip -cd mlton-*.tgz | tar xvf -

# execute under the extracted directory
./configure \
  --prefix=$HOME/opt \
  --with-gmp-include=/usr/local/include \
  --with-gmp-lib=/usr/local/lib
make
make install

Optionally, you can pass C compiler and linker flags to set MLton's -cc-opt and -link-opt compile-time options via XCFLAGS and XLDFLAGS environment variables:

./configure \
  XCFLAGS='-I/usr/local/include' \
  XLDFLAGS='-L/usr/local/lib'

If building from source cloned from Github, first generate the configure script (requires GNU Autotools):

autoreconf -vfi
# can now ./configure && make && make check && make install && make clean

To uninstall, simply delete the directory containing the MLton installation.

For more information, go to the MLton home page.

There are two mailing lists available.

• [email protected] MLton developers
• [email protected] MLton user community

doc (and share/doc) directory contents:

    README                  this file
    changelog               changelog
    cm2mlb/                 a utility for producing ML Basis programs in SML/NJ
    cmcat/                  a utility for producing whole programs in SML/NJ
    examples/               example SML programs
    guide/                  HTML MLton guide (copy of the MLton wiki)
    license/                license information
    mllex.pdf               user guide for mllex lexer generator
    mlton-guide.pdf         PDF version of MLton guide
    mlyacc.pdf              user guide for mlyacc parser generator

Submit an issue if you need any help. We welcome pull requests with bug fixes or changes.