Why do C compilers specify long to be 32-bit and long long to be 64-bit?

Question

Wouldn\'t it have made more sense to make long 64-bit and reserve long long until 128-bit numbers become a reality?

Answer 1

The c standard have NOT specified the bit-length of primitive data type, but only the least bit-length of them. So compilers can have options on the bit-length of primitive data types. On deciding the bit-length of each primitive data type, the compiler designer should consider the several factors, including the computer architecture.

here is some references: http://en.wikipedia.org/wiki/C_syntax#Primitive_data_types