Summary of problems detected using Purify
-----------------------------------------
Purify problems are marked in code comments with "PURIFY" keyword

Mode      Problem
--------  -------------------------------------------------------------------
bat       Possible 15985 byte memory leak from XPutImage.
cartoon   Possible 29756 byte memory leak from XPutImage.
flag      Sometimes have thousands of Array Bounds Reads and Free Memory Reads
          on XGetPixel call when image loaded is small.
fzort     Uninitialized memory read
life      Possible 132 byte memory leak from XPutImage
star      Possible 3264 byte memory leak detected only on SunOS 4.1.X
swirl     Possible 256 byte memory leak from XPutImage
tetris    Possible 120 byte memory leak from XPutImage
text3d    (unstable mode) Array Bounds Reads and Writes

There are also some Uninitialized Memory Reads that appear to be internal
to X11.

There are also some memory leaks detected in these source code files:
xlock/iostuff.c xlock/resource.c xlock/spline.c xmlock/option.c

MesaGL 2.3 fixes many cumulative leaks and uninitialized memory reads that
existed in MesaGL 2.2 and earlier MesaGL releases.  This affected all GL modes.
MesaGL 2.3 or newer is recommended since it fixes these memory leaks and runs
faster.  Cumulative means that the memory leaks occur each time the mode is run
when in random mode, which is why after some time it may crash xlock since it
runs out of available memory.

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Thanks to Tom Schmidt (tschmidt@micron.com) for the Purify logs.