Standard ML of New Jersey Release Notes

Standard ML of New Jersey
Release Notes
Version 110.86
May 2, 2019

SML/NJ HOME

  https://smlnj.org

FILES

  https://smlnj.org/dist/working/110.86/

## Summary

The main purpose of this release is to provide a stable checkpoint for a series of internal compiler changes, which are part of the effort to support 64-bit systems. In addition, however, it also contains a number of bug fixes and other improvements.

## Details

### Installation

While the installer for 110.86 works on macOS 10.14 Mojave, building from source requires some extra steps.

### SML/NJ Library

Renamed the function `CharBufferPP.openOut` to `openBuf`, and added the `TextPP` structure that supports pretty printing to either an output stream (like `TextIOPP`) or a character buffer (like `CharBufferPP`).

### ASDL

Further improvements to the new implementation of ASDL.

- The interface to file and memory picklers was unified for the SML view.

- Added support for S-Expression pickling for the SML view (unpickling has not yet been implemented).

- Significant editing of the documentation to make it more accurately reflect the implementation.

### Compiler

We have made a number of changes to internal representations and implementations as part of the preparation for supporting 64-bit targets. We summarize these below (see the change log for details).

- Moved CPS related code out of the FLINT directory and into its own `compiler/CPS` directory tree.

- Split out the utility code from the `CPS` structure into a new `CPSUtil` structure.

- Renamed the various CPS primitive constructors so as to be compatible with ASDL (i.e., changed symbolic and lower-case constructor names to upper-case identifiers).

- Moved the `F_SGN` constructor from the `fcmp` datatype to the `branch` datatype (and renamed it `FSGN`).

- Many changes to the internal representation of primitive operators.

We have also made improvements to the core 64-bit arithmetic operations.

Culled unused flags from the `Control` structure (mostly from `Control.CG`).

### Interactive System

The implementation of the `use` function in the REPL has been rewritten to fix bugs 193, 217, and 219. The semantics of `use` are as follows:

- If an invocation of `use` encounters a compilation error (either in the initial file or in a nested invocation of `use`), then the compiler error message will be printed and the call to `use` will immediately return `()`.

- If an invocation of `use` raises an exception during execution of the compiled code (either in the initial file or in a nested invocation of `use`), then the exception will be reported at the top-level.

- Otherwise, if no errors or uncaught exceptions are encountered, then `()` will be returned once the code in the used file has executed.

Note that any change to the global state or environment that occurs before an error is encountered, will not be rolled back. Also, wrapping calls to `use` in exception handlers or using `callcc` in combination with `use` may break it.

Files specified as command-line arguments to the sml command are treated as if `use` was invoked on them. If there is an error, then the error is reported and the sml command will terminate with a non-zero exit status (at least on Unix).

## Bugs

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

193 | SML/NJ does not print unhandled exceptions in loaded files
213 | `Int32.div` raises `Div` instead of `Overflow` when dividing `minInt` by `~1`
217 | Unhandled exceptions no longer print anything when inside used file
219 | "use" fails silently when a function inside a structure raises an exception

The following unnumbered bugs were also fixed:

- The `Word32.toInt` function did not raise `Overflow` when given an argument with its sign bit set in some cases (e.g., `Word32.toInt 0wx8002DE32;` would return `187954`).

## 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) |
| AIX |
Sparc | Solaris |
| Linux |
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) | Tested
| macOS 10.13 (High Sierra) | Tested
| macOS 10.14 (Mojave) | Tested
| Ubuntu 16.04.3 LTS | Tested
| 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.