## 3.3 Changes in the implementation that affect usability and performance

### 3.3.1 Compiler

- Register allocation (bugs 1291, 1070, 1329)

- Improved static analysis (bugs 87, 299, 654, 655)

- Code generation (bugs 464, 867, 1322): in particular, this fixes the occasional problems with complex andthen/orelse expressions

### 3.3.2 Unification

Failure in the unification of OFS (open feature structures) did not always untrail properly (bug 1314)

### 3.3.3 Distribution Subsystem

Distributed resources (distributed entities without a consistency protocol represented by a special resource token on remote sites) handled inproperly during local garbage collection (bug 1304)