Very Computer

by **W. John Gammag** » Sat, 03 Oct 1998 04:00:00

The following simple test program produces the attached "undefined
reference to `sin'" diagnostic message. I am using Red Hat 5.1 Linux.
This trig function is the only difficulty that I am experiencing in my
development.

It looks to me like I am either required to include file include an
include file in addition to the <math.h>. However, this is not required
on other UNIX systems. The man page for 'sin' does not specify an
include file in addition to the <math.h> file which I have included.

It certainly looks like a prototype issue. Am I missing something
obvious here? Your comments by e-mail are appreciated.

Regards, W. John Gammage

--------=[ begin code and diagnostic excerpt here ]=--------

jgammage /Users/jgammage/Programs/Hack ! ;) make math
cc math.c -o math

/tmp/cca003491.o: In function `main':
/tmp/cca003491.o(.text+0xe): undefined reference to `sin'
make: *** [math] Error 1

Test program:

#include <math.h>
double d_Scale;
main () {
d_Scale = sin( M_PI );

Quote:}

--------=[ end code and diagnostic excerpt here ]=--------

by **Aaron Cra** » Sat, 03 Oct 1998 04:00:00

Quote:> jgammage /Users/jgammage/Programs/Hack ! ;) make math
> cc math.c -o math

> /tmp/cca003491.o: In function `main':
> /tmp/cca003491.o(.text+0xe): undefined reference to `sin'
> make: *** [math] Error 1

Use `cc -o math math.c -lm'. You have to link the math library into your
program (-lm) and the `-lm' must come at the end of the command line (or at
least, after all the object files that need symbols it defines).

BTW, this is in the comp.lang.c FAQ list, `if only you had thought to look
there'; try <URL:http://www.eskimo.com/~scs/C-faq/top.html>.

--

by **Thomas Glanzman** » Sat, 03 Oct 1998 04:00:00

try to use the option -lm (linking with math lib).
next time please refer the man page of math lib (man math)

greetings tg

> The following simple test program produces the attached "undefined
> reference to `sin'" diagnostic message. I am using Red Hat 5.1 Linux.
> This trig function is the only difficulty that I am experiencing in my
> development.

> It looks to me like I am either required to include file include an
> include file in addition to the <math.h>. However, this is not required
> on other UNIX systems. The man page for 'sin' does not specify an
> include file in addition to the <math.h> file which I have included.

> It certainly looks like a prototype issue. Am I missing something
> obvious here? Your comments by e-mail are appreciated.

> Regards, W. John Gammage

> --------=[ begin code and diagnostic excerpt here ]=--------

> jgammage /Users/jgammage/Programs/Hack ! ;) make math
> cc math.c -o math

> /tmp/cca003491.o: In function `main':
> /tmp/cca003491.o(.text+0xe): undefined reference to `sin'
> make: *** [math] Error 1

> Test program:

> #include <math.h>
> double d_Scale;
> main () {
> d_Scale = sin( M_PI );
> }

> --------=[ end code and diagnostic excerpt here ]=--------

Very Computer

Q: Red Hat 5.1 Linux - 'C' math problem

Q: Red Hat 5.1 Linux - 'C' math problem

Q: Red Hat 5.1 Linux - 'C' math problem

Q: Red Hat 5.1 Linux - 'C' math problem