Data types
In many programming environments for C and C-derived languages on 64-bit machines, int variables are still 32 bits wide, but long integers and pointers are 64 bits wide. These are described as having an LP64 data model. This chapter assumes LP64, though other data models are available, see Table 5.1. The ARM ABI defines a number of basic data types for LP64. Some of these can vary between architectures, and are included in the following:
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