# V5002. OWASP. An empty exception handler. Silent suppression of exceptions can hide the presence of bugs in source code during testing.

Note: the diagnostic rule applies only to C++.

The PVS-Studio analyzer has detected an empty exception handler.

Here is the code:

    try {
      ...
    }
    catch (MyExcept &)
    {
    }

The code may not be incorrect. Although, it is very odd to suppress an exception by doing nothing. Such exception handling might conceal program defects and complicate the testing process.

Developers need to react to exceptions, for instance, add 'assert(false)':

    try {
      ...
    }
    catch (MyExcept &)
    {
      assert(false);
    }

Developers may use such constructs to return control from nested loops or recursive functions. However, exceptions are very resource-intensive operations and must be used for their intended purpose, i.e. for possible contingencies that must be handled at a higher level.

Developers can suppress exceptions in destructors that must not throw exceptions. However, it is often not quite clear what to do with exceptions in destructors, and the exception handler might be empty. The analyzer does not warn developers about empty handlers inside destructors:

    CClass::~ CClass()
    {
      try {
        DangerousFreeResource();
      }
      catch (...) {
      }
    }

This diagnostic is classified as:

CWE-1069 CWE-390 CWE-544 OWASP-7.4.2 CERT-ERR56-CPP