Defines the semantics of computer memory storage for the purpose of the C++ abstract machine.

The memory available to a C++ program is one or more contiguous sequences ofbytes. Each byte in memory has a uniqueaddress.

[edit]Byte

Abyte is the smallest addressable unit of memory. It is defined as a contiguous sequence of bits, large enough to hold

• the value of anyUTF-8 code unit (256 distinct values) and of

Similar to C, C++ supports bytes of sizes 8 bits and greater.

Thetypeschar,unsignedchar, andsignedchar use one byte for both storage andvalue representation. The number of bits in a byte is accessible asCHAR_BIT orstd::numeric_limits<unsignedchar>::digits.

[edit]Memory location

Amemory location is the storage occupied by theobject representation of either an object ofscalar type that is not abit-field, or the largest contiguous sequence of bit-fields of non-zero length.

Note: Various features of the language, such asreferences andvirtual functions, might involve additional memory locations that are not accessible to programs but are managed by the implementation.

struct S{char a;// memory location #1int b:5;// memory location #2int c:11,// memory location #2 (continued):0,        d:8;// memory location #3struct{int ee:8;// memory location #4} e;} obj;// The object “obj” consists of 4 separate memory locations

[edit]Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

[edit]See also

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