The Third Glasgow Workshop on Functional Programming was held in Ullapool, Scotland, 13-15th August 1990. Members of the functional programming groups at Glasgow and Stirling University attended the workshop together with a small number of invited participants from other universities and industry. The workshop was organised by Kei Davis, Jak Deschner, Kevin Hammond, Carsten Kehler Holst, John Hughes, Graham Hutton, and John Launchbury, all from Glasgow University. We are very grateful for the support of our industrial sponsors: British Telecom, Hewlett Packard, ICL and Software AG. Their financial help made the workshop possible. Thanks to Samson Abramsky, Tony Field, and Paul Kelly, all from Imperial College, for their help in refereeing many of the papers. Glasgow University The Programme Committee: December 1990 Simon Peyton Jones (chairman) Chris Hankin Carsten Kehler Holst John Hughes Graham Hutton Philip Wadler Contents Lifetime Analysis Guy Argo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compiling Laziness by Partial Evaluation Anders Bondorf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Strictness Analysis in 4D Kei Davis and Philip Wadler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 An Algorithmic and Semantic Approach to Debugging Cordelia Hall, Kevin Hammond and John O'Donnell . . . . . . . . . . . . . . . . . . . . 44 Abstract Interpretation of Term Graph Rewriting Systems Chris Hankin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Compile-Time Garbage Collection by Necessity Analysis Geoff W Hamilton and Simon B. Jones. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Improving Full Laziness Carsten Kehler Holst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Towards Binding-Time Improvement for Free Carsen Kehler Holst and John Hughes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Towards Relating Forwards and Backwards Analyses John Hughes and John Launchbury . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 PERs Generalise Projections for Strictness Analysis Sebastian Hunt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Functional Programming with Relations Graham Hutton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .