std.signal implementation is fundamentally incorrect

[dlangBugzillaToGithub]

verylonglogin.reg (@denis-sh) reported this on 2013-02-27T04:02:34Z

Transfered from https://issues.dlang.org/show_bug.cgi?id=9606

CC List

• Bastiaan

Description

`std.signal` implementation is written like it is called from a single thread or explicitly synchronized. The reality is on objects collecting GC calls dispose events of finalizing object from its thread. So `unhook` can be called in a middle of `emit`, `connect`, or `disconnect` freezed in other thread.

[dlangBugzillaToGithub]

verylonglogin.reg commented on 2013-02-27T04:03:21Z

As we can't lock GC (at least in `emit`) some sort of lock-free programming should be used here.

[dlangBugzillaToGithub]

verylonglogin.reg commented on 2013-02-27T06:03:54Z

A think-less fix just to prevent nasty random failures:
https://github.com/D-Programming-Language/phobos/pull/1179

[dlangBugzillaToGithub]

verylonglogin.reg commented on 2013-03-16T05:00:58Z

Added issue 4151 as a dependency as weak reference looks as the right way to fix this.