[ 2019-03-16; Daniel comments and updates wording ]

Hubert Tong pointed out that we do not have a statement about [U]INTPTR_{MIN|MAX} being optional. Interestingly, the C11 Standard does not say directly that the [U]INTPTR_{MIN|MAX} macros are optional, but this follows indirectly from the fact that intptr_t and uintptr_t are indeed optional. The updated wording therefore realizes Hubert's suggestion.

In addition, the reference document has been rebased to N4810, because that draft version contains an editorial change, which renames the term "range exponent" of integer types to "width", which is the vocabulary used below and also matches C's use.

Finally, Hubert Tong suggested the following rewording replacements of

If and only if the implementation defines such a typedef name, it also defines the corresponding macros.

to:

Each of the macros listed in this subclause is defined if and only if the implementation defines the corresponding typedef name.

and of

PRI macros that use the placeholder N are defined if and only if the implementation actually defines the corresponding typedef name in [cstdint.syn]. SCN macros that use the placeholder N are defined if and only if the implementation actually defines the corresponding typedef name and the implementation has a suitable fscanf length modifier for the type.

to:

Each of the macros listed in this subclause is defined if and only if the implementation actually defines the corresponding typedef name in [cstdint.syn].

Those changes have been applied as well.