Eric Blake wrote:
> Meanwhile, I'm committing this (POSIX states
> that the various *setjmp are allowed to be only a macro; but *longjmp must be
> linkable functions):
Thanks for the doc fixes. Most of this symbol / platform presence/absence
matrix was generated automatically. On some macro-like or inlined symbols
the results were not right.
Regarding _setjmp and _longjmp you say that they are "obsolete". I disagree
for two reasons:
1) On glibc systems, setjmp() does not save the signal mask, but when
_BSD_SOURCE is defined, setjmp() _does_ save the signal mask.
So if I want to save the registers but not the signal mask, independently
of the CFLAGS in use, I *must* use '_setjmp', not 'setjmp', on glibc
systems.
2) _setjmp is always faster or same-speed as setjmp; _setjmp can be 30 times
faster than setjmp. I did these benchmarks just two weeks ago, comparing
setjmp() versus _setjmp() versus sigsetjmp(.,0). (Times are in micro-
seconds.)
setjmp _setjmp sigsetjmp(.,0)
saves mask/time saves mask/time saves mask/time
Linux N 0.035 N 0.035 N 0.080
Linux -D_BSD_SOURCE Y 0.88 N 0.035 N 0.079
FreeBSD 6.2 Y 0.56 N 0.017 N 0.019
OpenBSD 4.0 Y 0.39 N 0.016 N 0.019
HP-UX 11 Y 1.88 N 0.13 N 1.98
See <http://article.gmane.org/gmane.lisp.clisp.devel/18227> for
details.
Conclusion: There's no adequate equivalent for _setjmp.
Bruno
