[csetjmp.syn]

# 17 Language support library [[support]](./#support)

## 17.14 Other runtime support [[support.runtime]](support.runtime#csetjmp.syn)

### 17.14.3 Header <csetjmp> synopsis [csetjmp.syn]

[🔗](#lib:jmp_buf)

#define __STDC_VERSION_SETJMP_H__ 202311Lnamespace std {using jmp_buf = *see below*; [[noreturn]] void longjmp(jmp_buf env, int val);}#define setjmp(env) *see below*

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/support.tex#L6431)

The contents of the header <csetjmp> are the same as the C
standard library header [<setjmp.h>](support.c.headers.general#header:%3csetjmp.h%3e "17.15.1 General [support.c.headers.general]")[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/support.tex#L6435)

The function signaturelongjmp(jmp_buf jbuf, int val) has more restricted behavior in this document[.](#2.sentence-1)

A setjmp/longjmp call pair has undefined
behavior if replacing the setjmp and longjmp by catch and throw would invoke any non-trivial destructors for any objects
with automatic storage duration[.](#2.sentence-2)

A call to setjmp or longjmp has undefined
behavior if invoked in a suspension context of a coroutine ([[expr.await]](expr.await "7.6.2.4 Await"))[.](#2.sentence-3)

See also: ISO/IEC 9899:2024, 7.13