Annex C (informative) Compatibility [diff]
C.8 C standard library [diff.library]
C.8.1 General [diff.library.general]
C.8.2 Modifications to headers [diff.mods.to.headers]
C.8.3 Modifications to definitions [diff.mods.to.definitions]
C.8.3.1 Types char8_t, char16_t, and char32_t [diff.char16]
C.8.3.2 Type wchar_t [diff.wchar.t]
C.8.3.3 Header <iso646.h> [diff.header.iso646.h]
C.8.3.4 Macro NULL [diff.null]
C.8.4 Modifications to declarations [diff.mods.to.declarations]
C.8.5 Modifications to behavior [diff.mods.to.behavior]
C.8.5.1 General [diff.mods.to.behavior.general]
C.8.5.2 Macro offsetof(type, member-designator) [diff.offsetof]
C.8.5.3 Memory allocation functions [diff.malloc]
C.8.1 General [diff.library.general]
Subclause [diff.library] summarizes the explicit changes in headers, definitions, declarations, or behavior between the C standard library in the C standard and the parts of the C++ standard library that were included from the C standard library.
C.8.3 Modifications to definitions [diff.mods.to.definitions]
C.8.3.1 Types char8_t, char16_t, and char32_t [diff.char16]
The types char8_t, char16_t, and char32_t are distinct types rather than typedefs to existing integral types.
The tokens char8_t, char16_t, and char32_t are keywords in C++ ([lex.key]).
They do not appear as macro or type names defined in .
C.8.3.2 Type wchar_t [diff.wchar.t]
The type wchar_t is a distinct type rather than a typedef to an existing integral type.
The token wchar_t is a keyword in C++ ([lex.key]).
It does not appear as a macro or type name defined in any of , , or .
C.8.3.4 Macro NULL [diff.null]
The macro NULL, defined in any of , , , , , , or , is an implementation-defined null pointer constant in C++ ([support.types]).
C.8.4 Modifications to declarations [diff.mods.to.declarations]
Header declares the names nullptr_t, byte, and to_integer, and the operators and operator templates in [support.types.byteops], in addition to the names declared in in the C standard library.
C.8.5 Modifications to behavior [diff.mods.to.behavior]
C.8.5.1 General [diff.mods.to.behavior.general]
C.8.5.2 Macro offsetof(type, member-designator) [diff.offsetof]
The macro offsetof, defined in , accepts a restricted set of type arguments in C++.
C.8.5.3 Memory allocation functions [diff.malloc]
The functions aligned_alloc, calloc, malloc, and realloc are restricted in C++.
Subclause [c.malloc] describes the changes.