Path: utzoo!attcan!uunet!aplcen!haven!umd5!cgs
From: cgs@umd5.umd.edu (Chris G. Sylvain)
Newsgroups: comp.os.minix
Subject: Compiler Quirks (/usr/lib/opt)
Keywords: peephole
Message-ID: <5715@umd5.umd.edu>
Date: 2 Dec 89 17:35:07 GMT
Organization: University of Maryland, College Park
Lines: 48


-- In our last episode ;-)  ---

> Problem #1: The construct "FILE *yyout = stdout;" generates the error
>   message "illegal initialisation".
>
> What's the best workaround?

I threw a "yyout = stdout;" in main() before I posted, but I wasn't convinced
that was "best". It was the consensus of the helpful replies that that was
exactly the workaround to use. Thanks to those who kindly responded!

-- Today's "episode":

Please note the "illegal initialisation" message was generated only for the
SECOND construct in the code. It had taken "FILE *yyin = stdin;" on the
previous line without complaining. In any case, yyin and yyout are now set
separately from their declarations.

Problem #2: /usr/lib/opt dies with the error message "assertion failed file
  peephole.c, line 172". Is there a way around opt? I've turned on as much
  cdecl debugging code as I can (opt runs out of memory!). I've chmem'ed opt
  as far as it'll go already (and back a bit again for safety).
     With the debugging strings in the code, it's now about 12k text, 17k data.

Problem #3: The substitute code for NOVARARGS apparently doesn't pick things
  off the stack properly. Could a ACK guru (or anyone familiar with the ACK
  stack layout) see what's wrong with these few lines ?

   /*
    *	it is assumed here that machines which don't have either
    *	<varargs.h> or <stdarg.h> will put its arguments on
    *	the stack in the "usual" way and consequently can grab
    *	the arguments using the "take the address of the first
    *	parameter and increment by sizeof" trick.
    */
# define VA_DCL(type,var)		(var) type var;
# define VA_START(list,var,type)	(list = (va_list)&(var) , (var))
# define va_arg(list,type)		((type *)(list += sizeof(type)))[-1]
# define va_end(p)			/* nothing */
typedef char *va_list;

..and I thought this'd be a piece of cake! Silly me!!-)
-- 
--==---==---==--
Rath: A sort of green pig
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