[536] in Athena Bugs
diff, all 4.3BSD releases
daemon@ATHENA.MIT.EDU (Mark W. Eichin)
Wed Jul 20 04:46:37 1988
Date: Wed, 20 Jul 88 04:46:04 EDT
From: Mark W. Eichin <eichin@ATHENA.MIT.EDU>
To: bugs@ATHENA.MIT.EDU
I have two files, which when diff is run over them, cause diff to loop
(or seem to.) They are in eichin:bugs/chess*.ps
% wc ch*
6770 6579 37807 chess_orig.ps
6769 6579 37806 chessm.ps
chessm has some brief changes. Other versions of the file produced
diff lists in a few seconds; these two cause diff to run for minutes,
reaching a fixed size fairly quickly (~300K on a vax, ~70K on an RT).
I'd also appreciate if someone could point me at some other
(algorithmically different?) diff that can produce a set of context
diffs... note that the 4.3BSD diff fails on both context and normal
diffs.
In the same directory is a copy of diff compiled -g for the vax from
/source/4.3/bin/diff; it exhibits the same problem.
If someone wants to learn a large amount about diff, they can try
this, otherwise it ought to get fed back to Berkeley. Feel free to
send them the files as well.
Mark Eichin
<eichin@athena.mit.edu>
SIPB Member & Project Athena ``Watchmaker''
