GNAT

Our Ada 95 technology is based on the GNAT compiler from New York University and ACT. We use the latest mature version, and customize it for our requirements.

For safety-critical applications, we restrict the language features that the compiler will accept in accordance with the restrictions defined in Appendix H of the Ada 95 Language Reference Manual. For a list of the restrictions that we apply, see Ada 95 Restrictions.

We also restrict the use of predefined Ada packages to those that are compatible with the restrictions, and that are required by application programmers.

Profiles

We support five restriction profiles:

1. The XGC profile for mission-critical applications
2. The Ravenscar profile, while includes a limited form of tasking
3. The APEX profile, which allows static tasks but no other tasking construct
4. The restricted profile, which excludes all forms of tasking
5. The no-runtime profile, which requires no run-time support at all.