Proof: Call a function with missing parameters doesn't work in C++

//file lib.cpp:
#include<cstdio>
void test(int a, int b) {
    printf("%d, %d\n", a, b);
}

//file main.cpp:
void test(int a); 
int main() {
    test(128);
}

//compile with `g++ -c -o lib.o lib.cpp; g++ lib.o main.cpp -o main`
//gives the following error:
//  /usr/bin/ld: /tmp/ccRGbh1g.o: in function `main':
//  main.cpp:(.text+0xa): undefined reference to `test(int)'
//  collect2: error: ld returned 1 exit status