Path: utzoo!mnetor!uunet!mcvax!eutrc3!wswietse
From: wswietse@eutrc3.UUCP (Wietse Venema)
Newsgroups: comp.unix.microport
Subject: Re: YAMB: problems with yacc?
Message-ID: <190@eutrc3.UUCP>
Date: 22 Mar 88 22:23:20 GMT
References: <437@splut.UUCP> <1107@ssc.UUCP>
Organization: Tech. Univ. Eindhoven, Neth.
Lines: 24
Keywords: won't do hoc1 right
Summary: it's a compiler bug!

In article <437@splut.UUCP>, jay@splut.UUCP (Jay Maynard) writes:
> I tried entering the program hoc1, from the book _The Unix Programming
> Environment_, and compiling it last night. It doesn't run: when fed an
> expression like 2+2, instead of printing 4, it prints 2. It appears to
> reproduce productions of the form:
> expr: expr '+' expr { $$ = $1 + $3 }...
> ...
> Am I bashing my head against YAMB (yet another Microport bug)?
> ...
> Jay Maynard, EMT-P, K5ZC...>splut!< | GEnie: JAYMAYNARD  CI$: 71036,1603
> ...

Well, actually it's a bug in the C compiler. Take a look of the 
assembly language generated by the compiler. Seems the compiler
generates incorrect 80287 opcodes. BTW we reported this problem
a long time ago (6 months) in the days of version 2.2. What 
happened to that bug list?

The problems should go away if you typedef the YACC stack as int.

-- 
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bitnet:	wswietse@heithe5	| Dept. of Mathematics and Computer Science
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