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Re: What am I doint wrong here?!?!
ummm... I tried it with the int/&int and it works for -O2, however, when
using the other way, I have compiled this with -g and no problems, as
soon as I use -O(1,2,3) I run into the core dump, why do I get a core
dumb than and not with -g?
TIA,
Chris
On Sun, 2003-02-23 at 13:56, Oscar Fuentes wrote:
> Chris Croswhite <ccroswhite at get2chip dot com> writes:
>
> > gcc 3.2.2 on x86 (686):
> > What am I doing wrong here:
> >
> > #include <math.h>
> > #include <stdio.h>
> >
> > int main () {
> > double val, num;
> > int *exp;
> >
> > val = 5.0/2.0;
> >
> > num = frexp(val, exp);
> >
> > printf("num is %g\n", val);
> >
> > return 1;
> > }
> >
> > gcc -static -O2 foo.c -o foo
> >
> > foo generates a dump.
>
> You provided a pointer, but it points nowhere. 'frexp' uses that
> pointer to store a value on the address it points to. Either you use
>
> /* We allocate a piece of memory and set 'exp' to point there */
> int *exp = (int*) malloc( sizeof(int) );
>
> val = 5.0/2.0;
>
> num = frexp(val, exp);
>
> or simply
>
> /* Use a plain variable */
> int exp;
>
> val = 5.0/2.0;
>
> /* We pass the address of 'exp' */
> num = frexp(val, &exp);
>
> HTH
--
Chris Croswhite <ccroswhite at get2chip dot com>
Get2Chip, Inc.