From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,c30642befcd7bf85 X-Google-Attributes: gid103376,public From: dewar@merv.cs.nyu.edu (Robert Dewar) Subject: Re: New GNAT ports (was Re: Ada and Automotive Industry) Date: 1997/01/09 Message-ID: #1/1 X-Deja-AN: 208699935 references: <5asvku$jtu$1@goanna.cs.rmit.edu.au> <32D39F37.7F1F@mailgw.sanders.lockheed.com> <5b252e$fk4$1@goanna.cs.rmit.edu.au> organization: New York University newsgroups: comp.lang.ada Date: 1997-01-09T00:00:00+00:00 List-Id: Richard said "I've poked around in the GNAT sources from time to time, but have never studied the whole thing. People who _have_ studied it: how long do you think it would take to understand the GNAT front end well enough to make an informed judgement about the difficulty of writing a non-GCC back end for it?" The front end of GNAT is pretty accessible. Read the documentation in sinfo and einfo to get a definition of the tree that is produced. Writing a production quality backend for any machine from scratch is a big project, of the order of person years for someone who knows what they are doing. Adapting an existing backend (if one is available that can be GPL'ed) is certainly a possibility, although sometimes clashes in assumptions can make such a project harder than expected. Note that the Ada Magic front end is more deliberately setup to provide for interfacing with multiple backends (this is obviously not a criterion for GNAT, since the assumption is that only one backend, GCC, will be used). Certainly building a small trial code generator hooked into the backend of GNAT is practical. I am planning on having my students in my compiler class do that this coming semester.