Annex C (informative) Compatibility [diff]

C.5 C standard library [diff.library]

C.5.2 Modifications to definitions [diff.mods.to.definitions]

C.5.2.7 Macro NULL [diff.null]

The macro NULL, defined in any of <clocale>, <cstddef>, <cstdio>, <cstdlib>, <cstring>, <ctime>, or <cwchar>, is an implementation-defined C++ null pointer constant in this International Standard ([support.types]).