Log Message:
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Add comment about why "((void) 0)" is used in copy macros.
Modified Files:
--------------
pgsql/src/backend/commands:
copy.c (r1.309 -> r1.310)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/copy.c?r1=1.309&r2=1.310)