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: 103376,99ab4bb580fc34cd X-Google-Attributes: gid103376,public From: kenner@lab.ultra.nyu.edu (Richard Kenner) Subject: Re: Q: access to subprogram Date: 1996/07/07 Message-ID: <4rpgco$iiq@news.nyu.edu>#1/1 X-Deja-AN: 167552034 references: organization: New York University Ultracomputer Research Lab newsgroups: comp.lang.ada Date: 1996-07-07T00:00:00+00:00 List-Id: In article Ronald Cole writes: >Not true. A single instance of GCC doesn't support multiple machine >targets (other than the -m options for some processor families). GCC >has to be recompiled to support different machine descriptions (that's >what the -b and -V options of gcc are for). I consider this as having >multiple backends. I don't think that's what Robert meant. The distinction he was trying to make is that GCC has only one piece that actually generates code (what is normally called the "back end") and that the config files modify what it does. In most compiler technologies, the config files say how to generate code, while in GCC (with some small number of exceptions) they describe the machine. >Many years ago, when asked about why he didn't >make GCC read loadable md files, Stallman answered that it would hurt >performance (both for the compiler and for the generated code) Yes, having loadable MD files would seriously hurt compiler performance, but is at least something that could be contemplated. By contrast, trying to load the tm.h file at runtime seems hopeless. >that was around the time when Stallman said that >writing what we now know as the bfd libraries would be "hard"). Yes, that's the original of the unoffical acronym of "BDF". However, note that this library is indeed far from trivial.