Affected subclause: [iterator.traits]
 Change: The specialization of 
iterator_traits for 
void* and
for function pointer types no longer contains any nested typedefs
.   Rationale: Corrects an issue misidentifying pointer types that are not incrementable
as iterator types
.   Effect on original feature: A valid C++ 2017 program that relies on the presence of the typedefs
may fail to compile, or have different behavior
.