Line 77, variable $R32 previously undefined.

All,

I received an error message from a phantom process the other day. It states that a register variable ($R32) is unassigned. At first blush I was confused, why would the run machine complain about a register variable that the compiler assigns? If I run VLIST on the program Line 77 shows $R32 being assigned a value. This process is run on many different part files (poor man's multi-threading) and I only get this message from one of the part file phantoms. It seems like the program is good. It would appear that if it were a data problem the compiler or run machine would complain about the problem data before it calls out a register variable.

The register number and line number were obfuscated to protect the innocent. The question still remains. 

Jon