Xref: news2.mv.net comp.os.msdos.djgpp:2060
From: elric AT wheel DOT ucdavis DOT edu (Jeffrey Taylor)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Bug hides with GDB.
Date: 21 Mar 1996 17:22:41 GMT
Organization: Davis Community Network - Davis, California, USA
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Message-ID: <4is391$obf@mark.ucdavis.edu>
References: <4iqeht$c1t AT news DOT manawatu DOT gen DOT nz>
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Malcolm Taylor (malcolm AT manawatu DOT gen DOT nz) wrote:
: Hi,
: 	I have a fairly annoying bug that is hiding when I use GDB to try to
: find it. The bug is that a search through a small database (using
: strcmp's) returns a NULL pointer (which normally means that it found
: nothing) when running normally, but when run through GDB the function
: finds the correct match. I was wondering if anyone had any ideas of
: what sort of functions or methods or bugs etc. could cause this effect
: (ie work when using a debugger). Basicly what is the difference in the
: environment between running normally and through a debugger.

: Thanks,
: Malcolm

Usually the physical addresses change, which means the content of 
uninitialized variables change.  This is especially spectacular with 
uninitialized pointers.  There are other, more subtle differences but 
this covers 90% and is independent of the debugger.  Timing is different, 
but I wouldn't expect that to affect a database program.

--
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Without my guitar, I am a poet without arms.
                        - Michael Bloomfield
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