I wrote this function:

static bool colorIsEmpty(const Color col)
{
    return (col[0] == 0 && col[1] == 0 && col[2] == 0 );
}

where Color is simply a float[3]; the function doesn't work if col[3] are all 0; but this works:

if(col[0] == col[1] == col[2] == 0) {
//gets called
}

however gcc gives me warning:

    cColorTest.c:212:5: warning: suggest parentheses around 
comparison in operand of ‘==’ [-Wparentheses]

so it would be nice if that function works,why it doesn't work?