how to use clang compile c file with math.h?

Question

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

int main()
{
    printf("%.81f\n", 1+2*sqrt(3)/(5-0.1));
    return 0;
}

output: /tmp/a4-4oU730.o: In function main': a4.c:(.text+0x4f): undefined reference tosqrt' clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

Try adding -lm for libm for math to your build command. That said, your code works fine for me using clang 4.1 on Mac OS.