@node longjmp
@subsection @code{longjmp}
@findex longjmp

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9799919799/functions/longjmp.html}

Gnulib module: ---

Portability problems fixed by Gnulib:
@itemize
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
The effects of this call are system and compiler optimization dependent,
since it restores the contents of register-allocated variables but not
the contents of stack-allocated variables.
@item
When longjumping out of a signal handler that was being executed on an
alternate stack (installed through @code{sigaltstack}),
on Hurd, FreeBSD, NetBSD, OpenBSD,
you need to clear the @code{SS_ONSTACK} flag in the @code{stack_t}
structure managed by the kernel.
@item
This function may crash when the invoker code was compiled with option
@code{_FORTIFY_SOURCE >= 2}
@c https://sourceware.org/PR32522
on Hurd.
@end itemize
