plpgsql.so undefined symbol error in pg_upgrade check

I am planning a 9.,2 to 9.4 upgrade using pg_upgrade with the link option.

Thanks first to Tom Lane for the prompt answer last week.  I have installed

9.4 in the same disk as 9.2 and running pg_upgrade with the --check option I get this error:

ERROR:  could not load library "/usr/local/pgsql_production/lib/plpgsql.so": /usr/local/pgsql_production/lib/plpgsql.so: undefined symbol: errcontext

This is pointing to the old 9.2 setup.  Of course running with the --check option I have not shut down 9.2 nor started up 9.4.

Thanks for your time and attention.

 
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