Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!umd5!brl-adm!brl-smoke!gwyn From: gwyn@brl-smoke.ARPA (Doug Gwyn ) Newsgroups: comp.lang.c Subject: Re: Pragma and noalias Keywords: Pragma, noalias Message-ID: <8176@brl-smoke.ARPA> Date: 28 Jun 88 16:59:46 GMT References: <381@proxftl.UUCP> Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB)) Organization: Ballistic Research Lab (BRL), APG, MD. Lines: 16 In article <381@proxftl.UUCP> bill@proxftl.UUCP (T. William Wells) writes: >My reasoning is this: in a correct program, where the #pragma >would be used, the variables referred to are IN FACT not >aliased. This means that the #pragma has NO effect on the >results of the program. Nice try, but no cigar. "Correct program" is logically prior to consideration of the effect of #pragma. The intention, I believe, was to specify that an arbitrary #pragma-free correct program could have an arbitrary #pragma inserted at an arbitrary (line boundary) point and would still be a correct program. This doesn't fit what you're trying to do. I have finally been convinced that whether or not #pragma is really allowed to affect the semantics of a correct program has not been clearly specified. Unless this is remedied, the only safe thing to do with #pragma will be to not use it.