Path: utzoo!mnetor!tmsoft!dptcdc!lethe!dave From: dave@lethe.UUCP (Dave Collier-Brown) Newsgroups: comp.arch Subject: Re: incremental compilation and code as data Summary: It'll be along presently... Message-ID: <2433@lethe.UUCP> Date: 3 May 89 03:04:49 GMT References: <89@ <46500061@uxe.cso.uiuc.edu> <1989May1.213448.11347@utzoo.uucp> Reply-To: dave@lethe.UUCP (Dave Collier-Brown) Organization: Interleaf Canada, News courtesy of Systems Software Lines: 37 In article <46500061@uxe.cso.uiuc.edu> mcdonald@uxe.cso.uiuc.edu writes: | I have been having a moderately heated (for Usenet, especially for | comp.lang.c) discussion with Doug Gwyn about architectures (hardware | or software) that prevent a given program from accessing the same | information as both code and data. In article <1989May1.213448.11347@utzoo.uucp> henry@utzoo.uucp (Henry | Spencer) writes: Without having seen the discussion, that I recall, I | think Doug's views are probably being misrepresented here. What he | probably was saying was not that it's a bad idea, but that not all | machines do it, and the ones that do it often have private wrinkles in | just how it should be done, so *relying* on it is a bad idea. | Incremental compilation is clearly important for a general-purpose | machine. But not everybody realized that, and not everybody was | originally trying to build general-purpose machines. Well, one part of the problem will have to be dealt with by anyone who wants to provide "public" or "shared" libraries in their version of Unix. The other part has been dealt with by people who wish to debug running programs. Regrettably, each problem has been solved (various ways) is isolation. Net result? "Ya kent git there from here. Ya got `t go back to Boston and start out on the other side of the river". By the way, you probebly don't need to access the memory as both code and data at the **same time** unless you actually intend to debug or test interactively. You might look at lisp implementations as an example of solutions to the problems, as even Multics Lisp could be a mixture of compiled and interpreted code. And that was a **while** ago! --dave (wheels reinvented while you wait) c-b -- David Collier-Brown, | {toronto area...}lethe!dave 72 Abitibi Ave., | Joyce C-B: Willowdale, Ontario, | He's so smart he's dumb. CANADA. 223-8968 |