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.

>
>
>
V685. The expression contains a comma. …
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

V685. The expression contains a comma. Consider inspecting the return statement.

Jan 31 2014

The analyzer has found that a value returned by a function might be incorrect as it contains the comma operator ','. This is not necessarily an error, but this code should be checked.

Here is an example of suspicious code:

int Foo()
{
  return 1, 2;
}

The function will return the value 2. The number 1 is redundant in this code and won't affect the program behavior in any way.

If it is just a typo, the redundant value should be eliminated:

int Foo()
{
  return 2;
}

But it may be possible sometimes that such a return value contains a genuine error. That's why the analyzer tracks such constructs. For example, a function call may have been accidentally removed during refactoring.

If this is the case, the code can be fixed in the following way:

int Foo()
{
  return X(1, 2);
}

Comma is sometimes useful when working with the 'return' operator. For example, the following code can be shortened by using a comma.

The lengthy code:

if (A)
{
  printf("hello");
  return X;
}

The shorter code:

if (A)
  return printf("hello"), X; // No warning triggered

We do not find the shorter code version smart and do not recommend using it. However, this is a frequent practice and such code does have sense, so the analyzer doesn't generate the warning if the expression to the left of the comma affects the program behavior.

This diagnostic is classified as: