Error with libgmp static link on Linux

Question

GMP docs say that static binding can provide a slight performance improvement.

I had a problem with its static link libgmp to my Linux systems. I narrowed down the question I have for a tiny test.

gmptest.c

#include <gmp.h>

int main(int argc, char** argv) {
    mpz_t foo;
    mpz_init(foo);
    return 0;
}

Makefile:

all: clean gmptest static

clean:
    rm -f *.s
    rm -f *.o
    rm -f gmptest
    rm -f static-gmptest

gmptest: Makefile gmptest.c
    gcc -std=c99 -O3 -lgmp gmptest.c -o gmptest

static: clean Makefile gmptest.c
    gcc -std=c99 -O3 -static /usr/lib/libgmp.a gmptest.c -o static-gmptest

The non-static binary is compiled and linked without any problems, but "Make static" produces:

gcc -std=c99 -O3 -static /usr/lib/libgmp.a gmptest.c -o static-gmptest
/tmp/ccWSFke9.o: In function `main':
gmptest.c:(.text+0x8): undefined reference to `__gmpz_init'
collect2: ld returned 1 exit status
make: *** [static] Error 1

The library exists:

chris@vostro:~/Dropbox/static$ ls -lA /usr/lib/libgmp.a 
-rw-r--r-- 1 root root 1041666 2010-02-26 13:20 /usr/lib/libgmp.a

I also tried -lgmp for static binding, but the error is the same.

This is all on Ubuntu 10.04 and 10.10 AMD64.

Can someone enlighten me regarding the obvious mistake I am making?

Thank,

Chris.

Answer 1

Try

 gcc -std=c99 -O3 -static gmptest.c -lgmp -o static-gmptest

.