-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Tatsuro MATSUOKA on 9/11/2007 2:49 PM: > My question is whether other possibilities to get fast sjlj-exception > EH in the cygwin.
I think you are misunderstanding a fundamental concept. sjlj exception handling is inherently slower than stack-tracing exception handling, because it must assume the worst and store the entire stack state (the 'sj' or setjump) prior to any call site where an exception might occur, whether or not an exception actually happens (the 'lj' or longjump part). Dwarf error handling, on the other hand, is a form of stack-tracing, where there is NO penalty UNLESS there was an exception. Exception handling is slower, because it must crawl backwards through the stack to find all catch points with handlers to run, but more efficient when there is no exception because you don't waste time saving state that never gets jumped to. In other words, the ONLY way to speed up octave is to avoid sjlj exceptions. And there are two ways to do that - either switch to stack-based exceptions (such as dwarf), or avoid exceptions to begin with. The octave maintainer has already expressed a reluctance to disable exceptions, and the current gcc for cygwin, 3.4.4, doesn't have a way to use anything other than sjlj, so you will just have to wait. > If there is no way to get the fast sjlj-exception EH, is it possible > to handle the 'gcc-dw2'? > I know there is 'gcc-dw2' for 4.2.1 version of gcc in the mingw. Have you not been reading this thread? gcc-dw2 for mingw is the dwarf-based exception handling build of gcc. Work is underway for building a similar gcc for cygwin, but doing it correctly involves building a shared libgcc, which isn't cleanly supported without gcc 4.3. - -- Don't work too hard, make some time for fun as well! Eric Blake [EMAIL PROTECTED] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFG5zLs84KuGfSFAYARAnNDAJ9XXEr8ynSI5381n00vw/m4RvVzIQCfbaIh 1DIv6noDwvFA8t9TfP0hrPQ= =RGFx -----END PGP SIGNATURE----- -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/