Date: Tue, 11 Apr 2006 23:07:35 +0000 From: "Jonathan Herriott" <herriojr@gmail.com> To: "Nicolas Blais" <nb_root@videotron.ca> Cc: freebsd-questions@freebsd.org Subject: Re: pow function working unexpectedly Message-ID: <6a56d69c0604111607l5fba5939pfc6461a99a2ceab3@mail.gmail.com> In-Reply-To: <200604111857.43171.nb_root@videotron.ca> References: <6a56d69c0604111554o587ce2c5ha1ff4ea20bbab0a4@mail.gmail.com> <200604111857.43171.nb_root@videotron.ca>
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Question then. Why would it work when I don't use variables if I
don't include the library? This question is just out of curiosity.
On 4/11/06, Nicolas Blais <nb_root@videotron.ca> wrote:
> On Tuesday 11 April 2006 18:54, Jonathan Herriott wrote:
> > I just want to make sure I'm not being stupid before I send in a bug.
> > The problem seems to be with gcc when using the pow function in the
> > math.h library. Here's code that works:
> >
> > #include <stdio.h>
> > #include <math.h>
> >
> > int main()
> > {
> > printf("%f\n", pow(2,3));
> > return 0;
> > }
> >
> >
> > Now, the following will not compile:
> >
> > #include <stdio.h>
> > #include <math.h>
> >
> > int main()
> > {
> > int x =3D 2; // I tried these as doubles too since the pow functio=
n
> > takes doubles
> > int y =3D 3;
> >
> > printf("%f\n", pow(x,y));
> > return 0;
> > }
> >
> > I compiled both programs using:
> > gcc test.c
> >
> > The second example gives the following error:
> >
> > /var/tmp//ccxtkMwv.o(.text+0x45): In function `main':
> > : undefined reference to `pow'
> >
> > If I comile with g++, I have no issues. Are these results that I
> > should have? If so, why? If not, I'm going to submit the bug on gcc
> > (or the linker, but I'm guessing it's the same group).
> >
> > Thanks,
> > Jonathan Herriott
>
> gcc -lm test.c works. You forgot to include the math library.
>
> --
> FreeBSD 7.0-CURRENT #1: Sat Apr 8 21:33:25 EDT 2006
> root@clk01a:/usr/obj/usr/src/sys/CLK01A
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>
>
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