X-Git-Url: https://sipb.mit.edu/gitweb.cgi/ikiwiki.git/blobdiff_plain/569545968a71179e216ee9e4ec3b9246aa89b304..638cef639d97ff9065e8a05f1a7923c0d51d6de4:/doc/bugs/recentchangesdiff_crashes_on_commits_which_remove_a_lot_of_files.mdwn

diff --git a/doc/bugs/recentchangesdiff_crashes_on_commits_which_remove_a_lot_of_files.mdwn b/doc/bugs/recentchangesdiff_crashes_on_commits_which_remove_a_lot_of_files.mdwn
index 663e7d4fe..b3578f26a 100644
--- a/doc/bugs/recentchangesdiff_crashes_on_commits_which_remove_a_lot_of_files.mdwn
+++ b/doc/bugs/recentchangesdiff_crashes_on_commits_which_remove_a_lot_of_files.mdwn
@@ -1,9 +1,46 @@
-[[plugin/recentchangesdiff]] causes rendering to segfault if a commit removes a lot of contents. I removed close to 400 files, total size of about 950Kb in a single commit and now `ikiwiki` segfaults on refresh and rebuild:
+[[plugins/recentchangesdiff]] causes rendering to segfault if a commit removes a lot of contents. I removed close to 400 files, total size of about 950Kb in a single commit and now `ikiwiki` segfaults on refresh and rebuild:
 
     [...]
     rendering recentchanges.mdwn
     [1]    5541 segmentation fault  ikiwiki --verbose --setup ikiwiki.setup --refresh
 
+If I disable the plugin, the segfault does not happen, but I have to remove `wc/recentchanges/*` or else it will crash just as well.
+
 This is reproducible, but I cannot provide the source code.
 
-If I disable the plugin, the segfault does not happen.
+> Can you provide a sanitised version of the source code? I've tried
+> ikiwiki on some files that are just large, and cannot reproduce any
+> problems, so it must be something in the specific file. (A perl bug is
+> also clearly involved here.) --[[Joey]]
+
+The tarball is at http://scratch.madduck.net/__tmp__recentchanges-segfault.tgz - unpack it in `/tmp` and `chdir()` to /tmp/cdt.taF18912, then run
+
+    ikiwiki --setup ikiwiki.setup
+    # segfaults
+    git checkout HEAD^
+    ikiwiki --setup ikiwiki.setup
+    # segfaults
+    rm -rf wc/recentchanges
+    ikiwiki --setup ikiwiki.setup
+    # works
+
+> I can reproduce it fine with that, thanks, and it's really looking like a
+> pure perl bug, that is triggered by markdown. Here's a simpler test case:
+
+	joey@kodama:/tmp>markdown < f
+	zsh: segmentation fault  markdown < f
+
+> Where f is a 6.3 mb file that I
+> extracted from ikiwiki's rendering pipeline.
+
+> It seems to be crashing at markdown line 345, which is a big nasty
+> `s///` statement.
+
+> The good news: markdown version 1.0.2~b8-2 does not trigger this perl bug.
+> I only see it with 1.0.1. (Bad news: Newer versions of markdown are
+> slooooooow, especially on such large files.)
+
+> I'm calling this [[done]] since I've filed [[!debbug 470676]] on perl, and
+> also have modified recentchangesdiff to only show the first 200 lines of
+> diff, which should be enough without bloating the recentchanges into
+> perl-crashing territory. --[[Joey]]