Index: IkiWiki/Rcs/
--- IkiWiki/Rcs/  (revision 4532)
+++ IkiWiki/Rcs/  (working copy)
@@ -275,6 +275,9 @@

    my $file = shift || q{--};

+   # Remove srcdir prefix to appease git-rev-list
+   $file =~ s/^$config{srcdir}\/?//;
    # Ignore error since a non-existing file might be given.
    my ($sha1) = run_or_non('git-rev-list', '--max-count=1', 'HEAD', $file);
    if ($sha1) {

I actually see a bug in this patch. :-) If srcdir = "foo" and the wiki contains a "foo/bar" and a "bar", this will make it, in the non-ctime case, get the sha1 of the wrong file, "bar", when "foo/bar" is asked for.

Better to strip the path out in getctime, I guess.