[bad.exception]

# 17 Language support library [[support]](./#support)

## 17.9 Exception handling [[support.exception]](support.exception#bad.exception)

### 17.9.4 Class bad_exception [bad.exception]

[ð](#lib:bad_exception)

namespace std {class bad_exception : public exception {public:// see [[exception]](exception "17.9.3 Class exception") for the specification of the special member functionsconstexpr const char* what() const noexcept override; };}

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/support.tex#L3981)

The classbad_exception defines the type of the object
referenced by the exception_ptr returned from a call to current_exception ([[propagation]](propagation "17.9.7 Exception propagation"))
when the currently active exception object fails to copy[.](#1.sentence-1)

[ð](#lib:what,bad_exception)

`constexpr const char* what() const noexcept override;
`

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/support.tex#L3995)

*Returns*: An implementation-defined ntbs[.](#2.sentence-1)
