Data Model (LP32 ILP32 LP64 LLP64 ILP64)

The 32-bit environment involves the "ILP32" data model because the C data type is a 32-bit int, a long, and a pointer. The 64-bit environment uses a different data model, where long and pointers are 64-bit, so they are called "LP64" data models.
Today all 64-bit UNIX-like platforms use the LP64 data model, while 64-bit Windows uses the LLP64 data model, except that the pointer is 64 bits, and the other base types do not change.

TYPE LP32 ILP32 LP64 ILP64 LLP64

CHAR 8 8 8 8 8

Short 16 16 16 16 16

INT 16 32 32 64 32

LONG 32 32 64 64 32

Long Long 64 64 64 64 64

POINTER 32 32 64 64 64

PS: Transfer from http://blog.csdn.net/foreverfresh/article/details/6731785

Data Model (LP32 ILP32 LP64 LLP64 ILP64)