C99标准:(Revision 2 20 October 1999)
6.7.2 Type specifiers
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To summarize this part: 32-bit CPUs are coming to need clean 64-bit integers, just as 16-bit CPUs came to need 32-bit integers, and the need for wider integers happens irrespective of other CPUs. Thus, 32-bit C has evolved from a common ILP32 model (int, long and pointers are 32 bits) to ILP32LL (ILP32 + 64-bit long long), and this still runs on 32-bit CPUs with sequences to emulate 64-bit arithmetic.
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