Is the minimum size of datatypes defined in bits or bytes?

Question

I know that the number of bits in a char is defined in CHAR_BIT from <limits.h> and that sizeof(char) is always 1. But what about other basic datatypes, are their sizes defined relative to CHAR_BIT?

For example the minimum size of an int in C is defined as 16 bits on Wikipedia, but on other sites like GeeksforGeeks the minimum size is defined as 2 bytes. Which definition is correct as a byte is not necessarily the same as 8 bits.

Answer 1

The minimum required range of values of a type is defined numerically, not in terms of bits or bytes. 5.2.4.2.1 Sizes of integer types <limits.h> says has definitions like:

• minimum value for an object of type short int
SHRT_MIN -32767 // -(2¹⁵ - 1)
• maximum value for an object of type short int
SHRT_MAX +32767 // 2¹⁵ - 1

All the type definitions happen to match up with implementing the types using either two's complement or sign-magnitude representation with a multiple of 8 bit bytes. But since they're just minimums, it doesn't require such representations.