In
computer programming
Computer programming is the process of performing a particular computation (or more generally, accomplishing a specific computing result), usually by designing and building an executable computer program. Programming involves tasks such as anal ...
, unreachable memory is a
block
Block or blocked may refer to:
Arts, entertainment and media Broadcasting
* Block programming, the result of a programming strategy in broadcasting
* W242BX, a radio station licensed to Greenville, South Carolina, United States known as ''96.3 ...
of
dynamically allocated memory where the
program that allocated the memory no longer has any reachable
pointer
Pointer may refer to:
Places
* Pointer, Kentucky
* Pointers, New Jersey
* Pointers Airport, Wasco County, Oregon, United States
* The Pointers, a pair of rocks off Antarctica
People with the name
* Pointer (surname), a surname (including a list ...
that refers to it. Similarly, an unreachable object is a dynamically allocated
object that has no reachable
reference
Reference is a relationship between objects in which one object designates, or acts as a means by which to connect to or link to, another object. The first object in this relation is said to ''refer to'' the second object. It is called a '' name'' ...
to it. Informally, unreachable memory is
dynamic memory
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when ...
that the program cannot reach directly, nor get to by starting at an object it can reach directly, and then following a chain of pointer references.
In dynamic memory allocation implementations that employ a
garbage collector, objects are reclaimed after they become unreachable. The garbage collector is able to determine if an object is reachable; any object that is determined to no longer be reachable can be
deallocated. Many
programming language
A programming language is a system of notation for writing computer programs. Most programming language