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In this noncompliant code example, the SomeClass destructor attempts to handle exceptions thrown from the destructor of the bad_member subobject by absorbing them.we presume the existence of a Bad class with a destructor that can throw, and although it violates this rule, we cannot modify it:

// Assume that this class is provided by a 3rd party and it is not something
// that can be modified by the user.
class Bad {
  ~Bad() noexcept(false);
};

In order to safely use the Bad class, the SomeClass destructor attempts to handle exceptions thrown from the Bad destructor by absorbing them:

class SomeClass {
  Bad bad_member;

public:
  ~SomeClass()
  try {
    // ...
  } catch(...) {
    // Handle the exception thrown from the Bad destructor.
  }
};

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A destructor should perform the same way whether or not there is an active exception. Typically, this means that it should invoke only operations that do not throw exceptions, or it should handle all exceptions and not rethrow them (even implicitly). This compliant solution differs from the previous noncompliant code example by having an explicit return statement in the SomeClass destructor. This statement prevents control from reaching the end of the exception handler. Consequently, this handler will catch the exception thrown by Bad::~Bad() when bad_member is destroyed, and it . It will also catch any exceptions thrown within the compound statement of the function-try-block, but the SomeClass destructor will not terminate by throwing an exception.

// Assume that this class is provided by a 3rd party and it is not something
// that can be modified by the user.
class Bad {
  ~Bad() noexcept(false);
};
 
class SomeClass {
  Bad bad_member;
public:
  ~SomeClass()
  try {
    // ...
  } catch(...) {
    // Catch exceptions thrown from noncompliant destructors of
    // member objects or base class subobjects.

    // NOTE: Flowing off the end of a destructor function-try-block causes
    // the caught exception to be implicitly rethrown, but an explicit
    // return statement will prevent that from happening.
    return;
  }
};

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