_setjmp
POSIX specification:
http://www.opengroup.org/onlinepubs/9699919799/functions/_setjmp.html
Gnulib module: —
Portability problems fixed by Gnulib:
Portability problems not fixed by Gnulib:
Note: A future revision of POSIX later than the 2008/2009 one may drop the
functions _setjmp and _longjmp. Still, in 2008, on all
systems which have _setjmp, it is the fastest way to save the
registers but not the signal mask (up to 30 times faster than setjmp
on some systems).