/in/foo.c: In function 'findMaxNeg':
/in/foo.c:15:12: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return index;
            ^~~~~
/in/foo.c: In function 'main':
/in/foo.c:33:5: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
     printf("%d %d", a[findMaxNeg(a, n1)], b[findMaxNeg(b, n2)]);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/in/foo.c:33:5: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]