[res.on.macro.definitions] (original) (raw)

16 Library introduction [library]

16.4 Library-wide requirements [requirements]

16.4.6 Conforming implementations [conforming]

16.4.6.3 Restrictions on macro definitions [res.on.macro.definitions]

The names and global function signatures described in [contents] are reserved to the implementation.

All object-like macros defined by the C standard library and described in this Clause as expanding to integral constant expressions are also suitable for use in #if preprocessing directives, unless explicitly stated otherwise.