functions in math.h

philgar · 02-22-2005, 10:06 PM

I'm trying to compile C using gcc. It doesn't recognize the sqrt() function. I've included the math.h file. Is there something I'm missing here?

Ilgar · 02-22-2005, 10:40 PM

Are you passing the -lm option to gcc (lm = link the math library)?

philgar · 02-22-2005, 10:44 PM

no i didn't. that works. thanks for your help.

Godsmacker777 · 03-27-2005, 05:08 PM

does this have to be passed for every library you would like to include?

what about the include statements in the .c file?

I have:

Code:

#include <stdio.h>
#include <math.h>

and when compiling (cc main.c), I get:

Code:

In function `main':
: undefined reference to `floor'

Should I de running "cc -lm main.c" ?
How exactly does this work?