Merged revisions 64549 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r64549 | brett.cannon | 2008-06-26 17:31:13 -0700 (Thu, 26 Jun 2008) | 7 lines

  warnings.warn_explicit() did not have the proper TypeErrors in place to prevent
  bus errors or SystemError being raised. As a side effect of fixing this, a bad
  DECREF that could be triggered when 'message' and 'category' were both None was
  fixed.

  Closes issue 3211. Thanks JP Calderone for the bug report.
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diff --git a/Misc/NEWS b/Misc/NEWS
index 0656041..0ba9a9c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -27,6 +27,11 @@
 Core and Builtins
 -----------------
 
+- Issue #3211: warnings.warn_explicit() did not guard against its 'registry'
+  argument being anything other than a dict or None. Also fixed a bug in error
+  handling when 'message' and 'category' were both set to None, triggering a
+  bus error.
+
 - Issue #3100: Corrected a crash on deallocation of a subclassed weakref which
   holds the last (strong) reference to its referent.