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 do not see the email in your inbox, please check if it is filtered to one of the following folders:

  • Promotion
  • Updates
  • Spam

Webinar: Parsing C++ - 10.10

>
>
>
V127. An overflow of the 32-bit variabl…
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

V127. An overflow of the 32-bit variable is possible inside a long cycle which utilizes a memsize-type loop counter.

Jul 21 2011

The analyzer detected a potential error: a 32-bit variable might overflow in a long loop.

Of course, the analyzer will not be able to find all the possible cases when variable overflows in loops occur.

But it will help you find some incorrect type constructs.

For example:

int count = 0;
for (size_t i = 0; i != N; i++)
{
  if ((A[i] & MASK) != 0)
    count++;
}

This code works well in a 32-bit program. The variable of the 'int' type is enough to count the number of some items in the array. But in a 64-bit program the number of these items may exceed INT_MAX and an overflow of the 'count' variable will occur. This is what the analyzer warns you about by generating the V127 message. This is the correct code:

size_t count = 0;
for (size_t i = 0; i != N; i++)
{
  if ((A[i] & MASK) != 0)
    count++;
}

The analyzer also contains several additional checks to make false reports fewer. For instance, the V127 warning will not be generated when we deal with a short loop. Here you are a sample of code the analyzer considers safe:

int count = 0;
for (size_t i = 0; i < 100; i++)
{
  if ((A[i] & MASK) != 0)
    count++;
}