Standard ML of New Jersey
Release Notes

Version 110.93
September 5, 2019


This release fixes a critical bug in the Windows implementation, as well as several other serious bugs. In addition, it contains a number of changes that are part of the 64-bit porting effort, but these should not affect 32-bit behavior.



While the installer for 110.93 works on macOS 10.14 Mojave, building from source requires some extra steps. Another issue that you may encounter when building on macOS 10.14 Mojave is an error message for a shell script of the form

  /bin/sh: bad interpreter: Operation not permitted

This error arises because the attribute is set on the shell script. To fix the problem, remove the attribute using the command

  xattr -d shell-script

and resume the build.


  • Restructured the CPS contraction phase to make the fusion of integer/word conversions more uniform.

  • Rewrote the expansion of the INLLSHIFT, INLRSHIFTL, and INLRSHIFT primops to correcly handle shift operations on types that are smaller than the default integer size. This change also allows the Word8 shift operations to be inlined.

  • Generalized code generation for conversions involving tagged integers/words, where the size is not the default integer size.

Runtime System

Made a bunch of changes to fix issues on 64-bit targets.


Here is a list of tracked bugs fixed (or closed) with this release, please see the bug tracker for more details.


OS.Process.sleep only works with whole numbers


Incremental Build fails on Windows

The following unnumbered bugs were also fixed:

  • Fixed a bug where Int32.fromLarge(Word32.toLargeInt 0wxffffffff) would return ~1 instead of raising Overflow.

  • Int64 comparisons were incorrect for the case where bit 31 of the low word was set.

  • Real.toManExp computed an exponent that was off by one. This bug also broke the Real.toLargeInt function.

  • Fixed a bug in the constant folding of arithmetic-right-shift operations.

Supported systems

We believe that SML/NJ will build and run on the following systems, but have only tested some of them:

Architecture Operating System Status

Power PC

Mac OS X 10.5 (Leopard)







x86 (32-bit)

Mac OS X 10.6 (Snow Leopard)

Mac OS X 10.7 (Lion)

Mac OS X 10.8 (Mountain Lion)

Mac OS X 10.9 (Mavericks)

Mac OS X 10.10 (Yosemite)

Mac OS X 10.11 (El Capitan)

macOS 10.12 (Sierra)


macOS 10.13 (High Sierra)


macOS 10.14 (Mojave)


Ubuntu 16.04.3 LTS


Other Linux variants

BSD variants

Windows 7

Windows 10

Cygwin (32-bit)

A note about 64-bit support

Apple is in the process of deprecating 32-bit support in macOS. With macOS 10.14 Mojave, compiling 32-bit applications, such as the SML/NJ runtime system, requires using an older SDK. The SML/NJ installer, however, works without issue on macOS 10.14 Mojave.

We have been working on 64-bit support since 110.82 we expect to have it in place before the release of macOS 10.15.