std::basic_ios<CharT,Traits>::~basic_ios
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                    |   virtual ~basic_ios();  | 
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Destroys the basic_ios object. rdbuf is not destroyed.
Notes
This destructor is virtual because the base class destructor, ios_base::~ios_base is virtual.
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| LWG 53 | C++98 | it was unspecified whether rdbuf is destroyed
 | 
it is not destroyed |