gcc in linux

[Fan Zhang]

Hi again,

I am new to compiling C programs in Linux/Unix. I wanted to compile a
program by using gcc, but it turned out that gcc does not know where to
locate the library being called.

The program is as follows,

#include <math.h>
int main()
{
double ss;
double ff;
ss=1.0;
ff=sin(ss);
printf("%6.4f\n",ff);
return 0;
}

The error message is,

/tmp/ccIV3yAb.o: In function `main':
/tmp/ccIV3yAb.o(.text+0x1e): undefined reference to `sin'

The command I used to compile is
gcc test.c

Could anyone please let me know where I did wrong? Thanks!

Fan

 

[Arthur J. O'Dwyer]

/tmp/ccIV3yAb.o: In function `main':
/tmp/ccIV3yAb.o(.text+0x1e): undefined reference to `sin'

The command I used to compile is
gcc test.c

This is practically word-for-word a FAQ.

http://www.eskimo.com/~scs/C-faq/q14.3.html

Read the whole thing.

-Arthur

 

[=?ISO-8859-1?Q?=22Nils_O=2E_Sel=E5sdal=22?=]

The error message is,

/tmp/ccIV3yAb.o: In function `main':
/tmp/ccIV3yAb.o(.text+0x1e): undefined reference to `sin'

The command I used to compile is
gcc test.c

Could anyone please let me know where I did wrong? Thanks!

You need to link with the math library which is called libm
so,
gcc test.c -lm
comp.os.linux.development.apps or comp.unix.programmer
is probably more appropriate for this Q though.

 

[E. Robert Tisdale]

I am new to compiling C programs in Linux/Unix.
I wanted to compile a program by using gcc
but it turned out that gcc does not know
where to locate the library being called.

The program is as follows,

#include <math.h>
int main()
{
double ss;
double ff;
ss=1.0;
ff=sin(ss);
printf("%6.4f\n",ff);
return 0;
}

The error message is,

/tmp/ccIV3yAb.o: In function `main':
/tmp/ccIV3yAb.o(.text+0x1e): undefined reference to `sin'

The command I used to compile is
gcc test.c

Could anyone please let me know where I did wrong? Thanks!

gcc test.c -lm

 

[Brian Gough]

I am new to compiling C programs in Linux/Unix. I wanted to compile a
program by using gcc, but it turned out that gcc does not know where to
locate the library being called. The command I used to compile is
gcc test.c. Could anyone please let me know where I did wrong? Thanks!

See http://www.network-theory.co.uk/docs/gccintro/gccintro_16.html
for information on linking with external libraries with gcc.

 

[Dan Pop]

See http://www.network-theory.co.uk/docs/gccintro/gccintro_16.html
for information on linking with external libraries with gcc.

Except that the sin function has nothing to do with *any* external
library: it's part of the standard C library.

Dan

 

[Jack Klein]

Hi again,

I am new to compiling C programs in Linux/Unix. I wanted to compile a
program by using gcc, but it turned out that gcc does not know where to
locate the library being called.

Linux is not UNIX, UNIX is not Linux.

The program is as follows,

#include <math.h>
int main()
{
double ss;
double ff;
ss=1.0;
ff=sin(ss);
printf("%6.4f\n",ff);
return 0;
}

The error message is,

/tmp/ccIV3yAb.o: In function `main':
/tmp/ccIV3yAb.o(.text+0x1e): undefined reference to `sin'

The command I used to compile is
gcc test.c

Could anyone please let me know where I did wrong? Thanks!

Fan

Despite the fact that Linux is not UNIX, gcc on Linux continues the
old UNIX tradition of pretending that part of the standard C library
is not part of the standard C library.

UNIX elitists do not like to make things easy for the uninitiated,
unwashed masses, even when the reason for a particular piece of
stupidity has been obsolete for 20 years.

 

[Darklight]

Linux is not UNIX, UNIX is not Linux.

try this gcc -Wall -lm test.c