13.17 Changes Introduced in Version 4.2.1

See 4.2.0 Changes for changes introduced in SICStus Prolog 4.2.

• 4.2.1 New Features: New Features
• 4.2.1 Bugs Fixed: Bugs Fixed
• 4.2.1 Other Changes: Other Changes
• 4.2.1 Known Issues: Known Issues