V1051. Consider checking for misprints. It's possible that an assigned variable should be checked in the next condition.

The analyzer has detected a situation where a variable is initialized or assigned a new value and is expected to be checked in the condition of a subsequent 'if' statement but another variable is checked instead.

This error is demonstrated by the following example:

int ret = syscall(....);
if (ret != -1) { .... }
....
int ret2 = syscall(....);
if (ret != -1) { .... }    // <=

Programmers often need to check the value returned by a function but use a wrong variable name in the condition of the 'if' statement. This mistake is typically made when you clone a code fragment but forget to modify the name of the variable in the condition. In the example above, the programmer forgot to change the name 'ret' to 'ret2'.

Fixed version:

int ret2 = syscall(....);
if (ret2 != -1) { .... }

The following example also demonstrates this mistake:

obj->field = ....;
if (field) ....;

Both the variable and the class member have the same name, which makes it easy to confuse one with the other.

This diagnostic is heuristic; it splits the names of variables into individual strings and compares the respective parts to conclude if there is a typo. It also performs a basic type check, aiming at reducing the number of false positives.

The diagnostic may often be triggered by code like this:

var->m_abc = ....;
var->m_cba = ....;
if (var->m_abc)      // <=
{
  ....
}

Fragments like this are usually correct. You can either suppress such warnings or swap the assignments so that the variable to be checked is assigned a value immediately before the 'if' statement:

var->m_cba = ....;
var->m_abc = ....;
if (var->m_abc)
{
  ....
}

Keeping the assignment and the check close to each other also makes the code more readable.

According to Common Weakness Enumeration, potential errors found by using this diagnostic are classified as CWE-754.


Bugs Found

Checked Projects
411
Collected Errors
14 100
This website uses cookies and other technology to provide you a more personalized experience. By continuing the view of our web-pages you accept the terms of using these files. If you don't want your personal data to be processed, please, leave this site. Learn More →
Accept