PolyML version 4.1.3 is now available. Below are a list of the major changes and bug fixes since the 4.1.2 release taken from the release notes. Version 4.1.3 has been available unofficially for a while but the release on the web site is now complete and this incorporates a few bug fixes which were only found during testing.

As usual I welcome comments and bug reports and I'll try to respond fairly quickly but the response will depend on pressure of other work. David

New features and Changes

Printing control switches New switches have been added to the Poly/ML.Compiler structure to control the printing of declarations. In both cases the default setting is true. Setting PolyML.Compiler.printInAlphabeticalOrder causes declarations to be printed in the order in which they were made rather than in alphabetical order. Setting PolyML.Compiler.printTypesWithStructureName to false causes types to be printed without the structure from which they came.

Large database support The support for large databases has been improved and it is now possible to create a database which will occupy all of the virtual memory reserved for it. The actual limits vary between operating systems and platforms but are typically around 400Mbytes.

To aid this the -S option when running the disc garbage-collector (-d option), introduced in 4.1.1, has been extended with -Smin and -Smax. The options can be written using either -s or -S and with or without a space. Setting a size is now "sticky" so if no -s/-S option is given the previous limits are retained rather than being reset to the default. The -Smax option sets the limits to the maximum space available. This space now depends only on the size reserved for any parent databases and not, as before, on the history of the database.

The -Smin option compacts the database into a size whose upper limit is set to the size actually in use before compaction. To make best use of it it is probably best to run it twice, once to compact the database and again to set the upper limits to the now reduced size. It is useful when a database has been created which will not be modified further but where child databases may be created. Compacting a database to the minimum size allows any child databases to occupy as much space as possible.

The disc garbage collection has been changed so that it is now possible to use all the address space. Previously it was always necessary to reserve a certain portion of the space to allow the database to be collected.

Bugs fixed

Mac OS X 10.2 Mac OS X 10.2 introduced a undocumented change to the kernel interface when delivering signals. This meant that the original binaries will not run on 10.2. This has now been fixed.

Crash on delivering console interrupt on PowerPC There was a bug in the Poly/ML process (lightweight thread) code on the PowerPC which caused a crash when a process terminated. This could happen when a user-installed signal handler was called, for example the console interrupt handler in Isabelle.

Crash in equality code An error in the compilation of the equality function meant that certain expressions involving equality could cause a crash. This has been fixed.