Bug in grep 2.5

[Matt Perry]

Hi.  I believe that I've found a bug in grep and wanted to report it.
I'm using grep 2.5.1 under Redhat Linux 7.3.  I'm not sure that this is an
official GNU version of grep as I couldn't find a version of it on the GNU
mirrors.  However, I was able to reproduce the problem with grep 2.5
which I downloaded and compiled from a GNU mirror.

The problem appears when using the -f option.  When executing:

  grep -f patternfile textfile

where patternfile is a 121605 byte file with 3685 lines and textfile is
a 13713485 byte file with 144160 lines.  After running for several days
and only printing several screenfuls out output, my system began to run
out of memory.  I noticed too late to see if grep was using all of the
RAM.

It seems that the more lines in the patternfile then the slower grep
will run.  Here's a chart with different run times:

lines  | run time
-------+-----------
100    | 0m1.875s
200    | 0m11.997s
300    | 0m39.365s
400    | 1m39.045s
500    | 4m39.141s
600    | 11m1.241s

and so forth.

I'd be happy to supply the two data files if you need them.

-- 
Matt Perry | matt at primefactor dot com