[ 2018-06-18 after reflector discussion ]

Priority set to 3

LWG 2192 changed the library specification so that you always get all the std::abs overloads for fundamental types if you get any of them.

Except that it missed one: <cinttypes> provides a std::abs (and std::div) overload for intmax_t if it's not long long (since LWG 1449). Presumably that one should also follow the <cstdlib>/<cmath> pattern and we should make the complete abs overload set available whenever any of the three headers is included? (And likewise we should make the complete std::div overload set available whenever either <cstdlib> or <cinttypes> is included.)