Proposed resolution:

In [c.math], table 108, section "Functions", add nanf and nanl just after the existing entry nan.

In the listing of [c.math], table 108: Header <cmath> synopsis I miss the following C99 functions (from 7.12.11.2):

float nanf(const char *tagp);
long double nanl(const char *tagp);

(Note: These functions cannot be overloaded and they are also not listed anywhere else)