Defined in header <new> | ||
---|---|---|
class bad_alloc; |
std::bad_alloc
is the type of the object thrown as exceptions by the allocation functions to report failure to allocate storage.
Inheritance diagram.
(constructor) | constructs a new bad_alloc object (public member function) |
operator= | replaces the bad_alloc object (public member function) |
what | returns the explanatory string (public member function) |
(1) | ||
bad_alloc() throw(); | (until C++11) | |
bad_alloc() noexcept; | (since C++11) | |
(2) | ||
bad_alloc( const bad_alloc& other ) throw(); | (until C++11) | |
bad_alloc( const bad_alloc& other ) noexcept; | (since C++11) |
Constructs a new bad_alloc
object with an implementation-defined null-terminated byte string which is accessible through what()
.
*this
and other
both have dynamic type std::bad_alloc
then std::strcmp(what(), other.what()) == 0
. (since C++11)
other | - | another exception object to copy |
bad_alloc& operator=( const bad_alloc& other ) throw(); | (until C++11) | |
bad_alloc& operator=( const bad_alloc& other ) noexcept; | (since C++11) |
Assigns the contents with those of other
. If *this
and other
both have dynamic type std::bad_alloc
then std::strcmp(what(), other.what()) == 0
after assignment. (since C++11).
other | - | another exception object to assign with |
*this
.
virtual const char* what() const throw(); | (until C++11) | |
virtual const char* what() const noexcept; | (since C++11) |
Returns the explanatory string.
(none).
Pointer to a null-terminated string with explanatory information. The string is suitable for conversion and display as a std::wstring
. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.
Implementations are allowed but not required to override what()
.
[virtual] | destroys the exception object (virtual public member function of std::exception ) |
[virtual] | returns an explanatory string (virtual public member function of std::exception ) |
#include <iostream> #include <new> int main() { try { while (true) { new int[100000000ul]; } } catch (const std::bad_alloc& e) { std::cout << "Allocation failed: " << e.what() << '\n'; } }
Possible output:
Allocation failed: std::bad_alloc
allocation functions (function) |
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