title: "Variable may be uninitialized when used here" Xcode compiler warning
body: <p>So I wrote this little <a href="https://projecteuler.net/problem=4" rel="nofollow noreferrer">program</a> that gives this warning despite the fact that I have the variable initialized, not a <a href="https://stackoverflow.com/questions/6813660/warning-uninitialized-variable-but-i-have-initialized-c-compiler-bug">duplicate question</a>.</p>
  
  <pre><code>int main(int argc, const char * argv[]) {
      @autoreleasepool {
  
          int num1, num2, product, largestProduct = 0;
  
          while (num2 &lt; 1000) {
  
              while (num1 &lt; 1000) {
  
                  product = num1 * num2;
  
                  if (isPalindrome(product)) {
  
                      largestProduct = product&gt;largestProduct?product:largestProduct;
                  }
  
                  num1++;
              }
  
              num1 = 0; //If I delete that line the warning disappears.
              num2++;
          }
  
         NSLog(@"%i", largestProduct);
  
      }
      return 0;
  }
  </code></pre>
  
  <p>The weird thing is if I delete that commented line the warning disappears, and if I initialize <code>num1</code> individually it also disappears. Am I doing something wrong or is that a bug in Xcode?</p>