From: Chris Jones <chris DOT jones AT ucl DOT ac DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: SIGSEGV problem with DJGPP (deleting array)
Date: Tue, 13 Apr 1999 22:24:49 GMT
Organization: Deja News - The Leader in Internet Discussion
Lines: 50
Message-ID: <7f0g7a$qg7$1@nnrp1.dejanews.com>
NNTP-Posting-Host: 128.40.205.1
X-Article-Creation-Date: Tue Apr 13 22:24:49 1999 GMT
X-Http-User-Agent: Mozilla/4.0 (compatible; MSIE 4.01; Windows 95)
X-Http-Proxy: 1.1 x9.dejanews.com:80 (Squid/1.1.22) for client 128.40.205.1
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

(repost - I think my newsserver's having some problems. Apologies for any
duplication)

Hello - I'm having a few hassles with DJGPP and wondered if anyone on this NG
could help. I've written a program which works fine when compiled and run with
g++ on a Solaris machine, but exits when the same source is compiled and run
with DJGPP. I've traced the problem to the function below (which had already
been successfully called once before) - any ideas?

The ESP is less than the EBP, which the FAQ suggests means the stack frame
has been overrun. However I'm afraid I don't know enough to fix the problem -
I've tried manually setting the stack size to no effect. Not that the prorgam
should be using anywhere near that much memory. Playing around with the code,
I think the error arises in the second delete command (on the second use of
the function), but I've no idea why.

Any help would be very much appreciated! TIA.

(In the function, the variable size and values of ptr[i] seem to be read OK.)

<quoted function>

// add_element function
void myVector::add_element()
{
        double *ptr2= new double [size+1];

        for(int i=0;i<(size+1);i++)
        {
                ptr2[i]=ptr[i];
        }
        ptr2[size+1]=0;
        delete [] ptr;
        size=size+1;
        double *ptr=new double [size];
        for(int i=0;i<size;i++)
        {
                ptr[i]=ptr2[i];
        }
        delete [] ptr2;
        return;
}

--
Chris Jones

"Everybody who believes in psychokinesis, raise my right hand"

-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/       Search, Read, Discuss, or Start Your Own