Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.java.programmer > #10926

Re: reading the JLS (17.4.5)

Newsgroups comp.lang.java.programmer
From Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at>
Subject Re: reading the JLS (17.4.5)
References <slrnjerm1c.fvg.avl@gamma.logic.tuwien.ac.at> <jckv1o$v1v$1@dont-email.me> <slrnjf1iug.fvg.avl@gamma.logic.tuwien.ac.at> <jcqlef$5rp$1@dont-email.me> <B5-dnV9Gn_2ncW3TnZ2dnUVZ_h6dnZ2d@earthlink.com>
Message-ID <slrnjf37mr.fvg.avl@gamma.logic.tuwien.ac.at> (permalink)
Date 2011-12-21 08:54 +0000

Show all headers | View raw

Patricia Shanahan <pats@acm.org> wrote:
> I think "happens-before" should be thought of as short for "must appear
> to happen before". As the JLS says "It should be noted that the presence
> of a happens-before relationship between two actions does not
> necessarily imply that they have to take place in that order in an
> implementation.

The JLS even explicitly spells out, that to an unrelated thread these
synchronized-with actions may even appear out of order. This is, what
confuses me:

T1: hb(A,B)  - not necessarily observed so by T2
T1,T2:  hb(B,C)

How would T2 "know" about hb(A,C), if it doesn't know hb(A,B) ?

Back to comp.lang.java.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

reading the JLS (17.4.5) Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-18 12:10 +0000
  Re: reading the JLS (17.4.5) markspace <-@.> - 2011-12-18 06:57 -0800
    Re: reading the JLS (17.4.5) Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-20 17:54 +0000
      Re: reading the JLS (17.4.5) markspace <-@.> - 2011-12-20 10:50 -0800
        Re: reading the JLS (17.4.5) Patricia Shanahan <pats@acm.org> - 2011-12-20 12:12 -0800
          Re: reading the JLS (17.4.5) Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-21 08:54 +0000
            Re: reading the JLS (17.4.5) Patricia Shanahan <pats@acm.org> - 2011-12-21 10:56 -0800
              Re: reading the JLS (17.4.5) markspace <-@.> - 2011-12-21 12:02 -0800
  Re: reading the JLS (17.4.5) Patricia Shanahan <pats@acm.org> - 2011-12-18 09:21 -0800
    Re: reading the JLS (17.4.5) Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-20 18:35 +0000
      Re: reading the JLS (17.4.5) Lew <lewbloch@gmail.com> - 2011-12-20 19:08 -0800
        Re: reading the JLS (17.4.5) Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-21 08:37 +0000
          Re: reading the JLS (17.4.5) Patricia Shanahan <pats@acm.org> - 2011-12-21 10:46 -0800
          Re: reading the JLS (17.4.5) markspace <-@.> - 2011-12-21 12:09 -0800

csiph-web