Our website uses cookies to enhance your browsing experience.
Accept
to the top
close form

Fill out the form in 2 simple steps below:

Your contact information:

Step 1
Congratulations! This is your promo code!

Desired license type:

Step 2
Team license
Enterprise license
** By clicking this button you agree to our Privacy Policy statement
close form
Request our prices
New License
License Renewal
--Select currency--
USD
EUR
* By clicking this button you agree to our Privacy Policy statement

close form
Free PVS‑Studio license for Microsoft MVP specialists
* By clicking this button you agree to our Privacy Policy statement

close form
To get the licence for your open-source project, please fill out this form
* By clicking this button you agree to our Privacy Policy statement

close form
I am interested to try it on the platforms:
* By clicking this button you agree to our Privacy Policy statement

close form
check circle
Message submitted.

Your message has been sent. We will email you at


If you haven't received our response, please do the following:
check your Spam/Junk folder and click the "Not Spam" button for our message.
This way, you won't miss messages from our team in the future.

>
>
>
V612. Unconditional 'break/continue/ret…
menu mobile close menu
Analyzer diagnostics
General Analysis (C++)
General Analysis (C#)
General Analysis (Java)
Micro-Optimizations (C++)
Diagnosis of 64-bit errors (Viva64, C++)
Customer specific requests (C++)
MISRA errors
AUTOSAR errors
OWASP errors (C#)
Problems related to code analyzer
Additional information
toggle menu Contents

V612. Unconditional 'break/continue/return/goto' within a loop.

Aug 13 2013

The analyzer has detected an odd loop. One of the following operators is used in the loop body: break, continue, return, goto. These operators are executed always without any conditions.

Consider the following corresponding examples:

do {
  X();
  break;
} while (Foo();)

for (i = 0; i < 10; i++) {
  continue;
  Foo();
}

for (i = 0; i < 10; i++) {
  x = x + 1;
  return;
}

while (*p != 0) {
  x += *p++;
  goto endloop;
}
endloop:

The above shown examples of loops are artificial, of course, and of little interest to us. Now let's look at a code fragment found in one real application. We have abridged the function code to make it clearer.

int DvdRead(....)
{
  ....
  for (i=lsn; i<(lsn+sectors); i++){
    ....
//    switch (mode->datapattern){
//    case CdSecS2064:
      ((u32*)buf)[0] = i + 0x30000;
      memcpy_fast((u8*)buf+12, buff, 2048); 
      buf = (char*)buf + 2064; break;
//    default:
//      return 0;
//    }
  }
  ....
}

Some of the lines in the function are commented out. The trouble is that the programmer forgot to comment out the "break" operator.

When there were no comments, "break" was inside the "switch" body. Then "switch" was commented out and the "break" operator started to finish the loop earlier than it should. As a result, the loop body is executed only once.

This is the correct code:

buf = (char*)buf + 2064; // break;

Note that the V612 diagnostic rule is rather complicated: a lot of cases are accounted for, when using the break/continue/return/goto operator is quite correct. Let's examine a few cases when the V612 warning don't generated.

1) Presence of a condition.

while (*p != 0) {
  if (Foo(p))
    break;
}

2) Special methods used in macros usually:

do { Foo(x); return 1; } while(0);

3) Passing the 'continue' operator using 'goto':

for (i = 0; i < 10; i++) {
  if (x == 7) goto skipcontinue;
  continue;
skipcontinue: Foo(x);
}

There are other methods possible which are used in practice and are unknown to us. If you have noticed that the analyzer generates false V612 warnings, please write to us and send us the corresponding samples. We will study them and try to make exceptions to these cases.

This diagnostic is classified as:

You can look at examples of errors detected by the V612 diagnostic.