Launchpad has imported 3 comments from the remote bug at http://sourceware.org/bugzilla/show_bug.cgi?id=6966.
If you reply to an imported comment from within Launchpad, your comment will be sent to the remote bug automatically. Read more about Launchpad's inter-bugtracker facilities at https://help.launchpad.net/InterBugTracking. ------------------------------------------------------------------------ On 2008-10-19T01:29:34+00:00 Bugzilla-t wrote: hsearch references Kunth vol. 3 6.4 on "open addressing" but the code does implement the algorithm from Knuth. Instead of generating the second hash from the first, the code generates the second hash from the first index. Because this hash is then used to step the index, the result is that the first index generated is (almost) always the same. This partly defeats the purpose of using a secondary hash. I say "almost" because it happens for all but 2 of the possible index values in any given table. For example, in a table of size 11, all secondary probes will start at index 10 unless the inital hash produced 9 or 10. This was reported on news:comp.lang.c by James Dow Allen and I decided to check on it. I have a simple patch but I am not sure of the procedure for posting patches to glibc. Reply at: https://bugs.launchpad.net/glibc/+bug/367537/comments/0 ------------------------------------------------------------------------ On 2008-10-19T01:33:40+00:00 Bugzilla-t wrote: Created attachment 3006 Suggested fix. The patch suggests two related changes. First, that idx be set from hval without reducing havl % htab->size. hval2 can now be derived from hval without generating the same probe sequence all the time. Secondly, a new variable must be used to detect the wrap-around, since hval no longer contains the initial value of idx. Reply at: https://bugs.launchpad.net/glibc/+bug/367537/comments/1 ------------------------------------------------------------------------ On 2008-11-01T15:37:54+00:00 Drepper-fsp wrote: Applied to cvs. Reply at: https://bugs.launchpad.net/glibc/+bug/367537/comments/2 ** Changed in: glibc Importance: Unknown => Low -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/367537 Title: [jaunty] Segmentation fault in hsearch_r of glibc-2.9 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
