Xref: utzoo comp.fonts:386 comp.sys.mac:22379
Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!mailrus!uflorida!usfvax2!pollock
From: pollock@usfvax2.EDU (Wayne Pollock)
Newsgroups: comp.fonts,comp.sys.mac
Subject: LightSpeed Pascal 1.11 bug
Message-ID: <1151@usfvax2.EDU>
Date: 29 Oct 88 05:02:24 GMT
Reply-To: pollock@usfvax2.UUCP (Wayne Pollock)
Organization: University of South Florida at Tampa
Lines: 46
References:

Below is a LSP program (re-pretty-printed to save screen space; why oh why
can't I turn this option off?).  The two copies are identical except for the
keyword "packed" in the type statement.  Was this ever a tough bug to find!
(I thought I had an error in my program, which was over 1300 lines long.)

PROGRAM mojo (output);
	TYPE y = RECORD
		    a : integer;
		    b : 0..2047
		 END;
	VAR  x : y;
BEGIN
	x.b := 255;	writeln(x.b);
	x.b := 256;	writeln(x.b);
	x.b := 257;	writeln(x.b)
END.
(************************** GOOD RESULTS ***********************)
     255
     256
     257


PROGRAM mojo (output);
	TYPE y = PACKED RECORD
		    a : integer;
		    b : 0..2047
		 END;
	VAR  x : y;
BEGIN
	x.b := 255;	writeln(x.b);
	x.b := 256;	writeln(x.b);
	x.b := 257;	writeln(x.b)
END.

(************************** BAD RESULTS ***********************)

     255
       0
       1

Anyone know a fix for this?  It seems that by packing a subrange, LSP
allocates only one byte for the range even if the size of the range is
greater than 256!

Wayne Pollock (The MAD Scientist)	pollock@usfvax2.usf.edu
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