std::bad_alloc

C++

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Regular expressions library (C++11)

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Technical Specifications

Utilities library

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pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
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Dynamic memory management

Smart pointers unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (until C++17) owner_less (C++11) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) Allocators allocator allocator_traits (C++11) allocator_arg_t (C++11) allocator_arg (C++11) uses_allocator (C++11) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) Memory resources pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17) pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17)

Uninitialized storage uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) destroy_at (C++17) raw_storage_iterator (until C++20) get_temporary_buffer (until C++20) return_temporary_buffer (until C++20) Garbage collection support declare_reachable (C++11) undeclare_reachable (C++11) declare_no_pointers (C++11) undeclare_no_pointers (C++11) pointer_safety (C++11) get_pointer_safety (C++11) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) C Library malloc aligned_alloc (C++17) calloc realloc free Low level memory management

Low level memory management

Functions

operator newoperator new[]

operator deleteoperator delete[]

get_new_handler (C++11)

set_new_handler

Classes

bad_alloc

bad_array_new_length (C++11)

nothrow_t

align_val_t (C++17)

destroying_delete_t (C++20)

Types

new_handler

Objects

nothrow

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

Member functions

(constructor)	constructs the bad_alloc object (public member function)
operator=	replaces a bad_alloc object (public member function)
what	returns explanatory string (public member function)

std::bad_alloc::bad_alloc

bad_alloc();

Constructs new bad_alloc object with an implementation-defined null-terminated byte string which is accessible through what().

Parameters

(none)

Exceptions

(none)	(until C++11)
noexcept specification: noexcept	(since C++11)

std::bad_alloc::operator=

bad_alloc& operator=( const bad_alloc& other );

Assigns the contents of other.

Parameters

other

-

another exception object to assign

Return value

*this

Exceptions

(none)	(until C++11)
noexcept specification: noexcept	(since C++11)

std::bad_alloc::what

virtual const char* what() const;

Returns the explanatory string.

Parameters

(none)

Return value

Pointer to a null-terminated string with explanatory information.

Exceptions

(none)	(until C++11)
noexcept specification: noexcept	(since C++11)

Inherited from std::exception

Member functions

(destructor) [virtual]	destroys the exception object (virtual public member function of std::exception)
what [virtual]	returns an explanatory string (virtual public member function of std::exception)

Example

Run this code

#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

See also

operator newoperator new[]

allocation functions (function)