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V705. It is possible that 'else'...
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V705. It is possible that 'else' block was forgotten or commented out, thus altering the program's operation logics.

08 Sep 2014

This diagnostic is similar to V628 but deals with the else branch of the if operator. The analyzer has detected a suspicious code fragment which may be a forgotten or incorrectly commented else block.

This issue is best explained on examples.

if (!x)
  t = x;
else

z = t;

In this case, code formatting doesn't meet its logic: the z = t expression will execute only if (x == 0), which is hardly what the programmer wanted. A similar situation may occur when a code fragment is not commented properly:

if (!x)
  t = x;
else
  //t = -1;
z = t;

In this case, we either need to fix the formatting by turning it into something more readable or fix the logic error by adding a missing branch of the if operator.

However, there are cases when it's difficult to figure out if such code is incorrect or it's just stylization. The analyzer tries to reduce the number of false positives related to stylization through heuristic analysis. For example, the following code won't trigger the diagnostic rule:

if (x == 1)
  t = 42;
else
 
if (x == 2)
  t = 84;
else

#ifdef __extended__x
if (x == 3)
  t = 741;
else
#endif

  t = 0;

This diagnostic is classified as:

You can look at examples of errors detected by the V705 diagnostic.