208) Why do I get so many uninitilized memory read (UMR) errors when

I run Purify[tm] on my Motif programs?

[Last modified: July 96]

Answer:  Purify's reports are suggestions and do not always indicate real
bugs.  The X libraries frequently allocate dynamic memory, e.g., for attribute
or event structures, but don't explicitly initialize all of the memory.  X
keeps track of which structure fields are valid via a union type or a mask.
When X tries to copy or write the memory (part of which is uninitialized) as
one block, Purify reports a UMR.  This is not a bug and you can safely supress
or ignore the report.  Yes, X could initialize the unused field, but since
this happens alot, the needless operation could negatively affect your
performance.

Ken Lee, http://www.rahul.net/kenton/.