[pypy-commit] stmgc queue: Aaaaaaaa ok found the next bug

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: queue
Changeset: r1870:10bb05551db5
Date: 2015-06-18 21:23 +0200
http://bitbucket.org/pypy/stmgc/changeset/10bb05551db5/

Log:	Aaaaaaaa ok found the next bug

diff --git a/c8/stm/queue.c b/c8/stm/queue.c
--- a/c8/stm/queue.c
+++ b/c8/stm/queue.c
@@ -250,6 +250,11 @@
     }
 
  retry:
+    /* careful, STM_SEGMENT->segment_num may change here because
+       we're starting new transactions below! */
+    seg = &queue->segs[STM_SEGMENT->segment_num - 1];
+    assert(!seg->added_in_this_transaction);
+
     /* can't easily use compare_and_swap here.  The issue is that
        if we do "compare_and_swap(&old_entry, entry, entry->next)",
        then we need to read entry->next, but a parallel thread