The size of basic data types
This table gives the size and natural alignment of the basic data types in ARM C or C++.
| Type | Size in bits | Natural alignment in bytes |
|---|---|---|
| char | 8 | 1 (byte-aligned) |
| short | 16 | 2 (halfword-aligned) |
| int | 32 | 4 (word-aligned) |
| long | 32 | 4 (word-aligned) |
| long long | 64 | 8 (doubleword-aligned) |
| float | 32 | 4 (word-aligned) |
| double | 64 | 8 (doubleword-aligned) |
| long double | 64 | 8 (doubleword-aligned) |
| All pointers | 32 | 4 (word-aligned) |
| bool (C++ only) | 8 | 1 (byte-aligned) |
| _Bool (C only[1]) | 8 | 1 (byte-aligned) |
| wchar_t (C++ only) | 16 | 2 (halfword-aligned) |
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