[diff.mods.to.headers]

# Annex C (informative) Compatibility [[diff]](./#diff)

## C.8 C standard library [[diff.library]](diff.library#diff.mods.to.headers)

### C.8.2 Modifications to headers [diff.mods.to.headers]

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/compatibility.tex#L3691)

For compatibility with the C standard library,
the C++ standard library provides the C headers enumerated
in [[support.c.headers]](support.c.headers "17.15 C headers")[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/compatibility.tex#L3696)

There are no C++ headers for the C standard library's headers<stdnoreturn.h> and <threads.h>,
nor are these headers from the C standard library headers themselves part of C++[.](#2.sentence-1)

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/compatibility.tex#L3701)

The C headers [<complex.h>](complex.h.syn#header:%3ccomplex.h%3e "17.15.2 Header <complex.h> synopsis [complex.h.syn]") and[<tgmath.h>](tgmath.h.syn#header:%3ctgmath.h%3e "17.15.6 Header <tgmath.h> synopsis [tgmath.h.syn]") do not contain any of the content from
the C standard library and instead merely include other headers from the C++
standard library[.](#3.sentence-1)