A data model defines the sizes assigned to standard data types. It is important to understand the data models used by your implementation. However, if your code depends on any assumptions not guaranteed by the standard, you should provide static assertions (see DCL03-AC. Use a static assertion to test the value of a constant expression) to ensure that your assumptions are valid. Assumptions concerning integer sizes may become invalid, for example, when porting from a 32-bit architecture to a 64-bit architecture.
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