The following thread is being moved from xemacs-patches. Please keep
Torsten in the CCs, until Michael checks in, Torsten is the expert.
A few comments from the immoderator:
1. Please don't continue threads on xemacs-patches, even if others
do. I'd like to put a 'bot in place, but until then we depend on your
cooperation.
2. Please do use report-emacs-bug. It puts a lot of junk in, most of
it is not relevant, but it's better to have junk most of the time than
not have the information on the once a week or more occasion when it
would be helpful. It's especially nice when professionals do it; then
the average user will look and say, "oh, that's how the pros do it."
3. 21.4.6 is in prerelease. See the XEmacs-beta archives for the
announcement.
4. I don't know about recent versions, but as of Win NT 3.51 it was
possible to ask the OS to allocate a segment of 0xFFFFFFFF bytes, and
it would give it to you, wrapping right around 0. People on the DJGPP
list used to use this to implement fast graphics. I saw that and ran
for Linux as fast as my legs would carry me. No, "NT" was not a typo.
Never used that exploit myself, but it was confirmed by trustworthy
observers.
As for the bug itself, I've queried the person responsible for the
patch implementing the submatch argument (which was introduced by the
GNU Emacs project several years after we put something else there :(
). It's quite possible I screwed up the application somehow in an
early release.
Thanks to Torsten's analysis and patch it seems highly likely we
should have a fix in time for 21.4.6. We may be able to catch some
other bugs due to bogus dereferences, too. It seems pretty evil to
move a dereference that might segfault before the test to determine
whether it will segfault :-( Bad GCC, bad bad bad GCC!
Subject: Topics
Topics:
Fixing evil replace-match
Re: Fixing evil replace-match
Re: Fixing evil replace-match
Re: Fixing evil replace-match
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