From: "jansb000" <jansb000 AT wxs DOT nl>
Newsgroups: comp.os.msdos.djgpp
Subject: Need help with very nasty bug
Date: Wed, 11 Jul 2001 21:40:21 +0200
Organization: Planet Internet
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

In a program that I am working on I have a class that looks like this:

class MAPTILE  {
 private:
   BYTE  tile_idx;
   BYTE  fringe_idx;
   BYTE  build_idx;
   BYTE  top_idx;
   PROPS props;    // typedef to STL: bitset<32> props
   // ULONG spr;
 public:
   // Constructors ...
   // Destructor ...
   };

All test programs using this class work as they should and I even build a
working application with it.

Recently I added the line "ULONG spr" and to my suprise the application that
I spoke about doesn't work any more. Even when I recompile all source files,
generating new .o files.

My program is now quite large and I have no clue as where I should start
with finding the bug. I fail to understand how this one line can introduce a
bug. Note that I made no other changes apart from this single line. I even
didn't change the constructor and destructor.

Any tips?

PS: All code can be found at sourceforge: http://sf.net/projects/wcs-jabe by
following the links to CVS. The working application can be downloaded from
sourceforge too. It is a MAP editor.