math.h error

warun · 10-19-2008, 01:11 AM

hello everyone,

i am using slackware 12.1. i get this error while compiling c/c++ programs with math header.

/tmp/ccqG44Ak.o: In function `main':
try.c

.text+0x21): undefined reference to `cos'
collect2: ld returned 1 exit status

it worked fine in slackware 12.0. why is it so and is there any change in slackware 12.1 that i should be aware of?

thanks in advance....

paulsm4 · 10-19-2008, 01:25 AM

Hi -

#include <math.h> is a compile-time thing. You also need to add "-lm" to link the math library into your executable.

Try something like this:

Quote:

gcc -o myprog myprog.c -lm

'Hope that helps .. PSM

warun · 10-19-2008, 02:47 AM

hey thanks, that worked