AIX GDB fails to recognize core files

[sctguest sctguest]

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This GDB was configured as "powerpc-ibm-aix4.3.3.0"

compiled as shown fails to recognize core files that the system's DBX does 
recognize.

It also reports this error after start-up:

"/usr/lib/libpthreads.a": not in executable format: File format not recognized.

Marv Graham