Fix for lack of va_copy() on certain Windows versions
Fix for lack of va_copy() on certain Windows versions

Based-on-patch-by: David Rowley <c9d9fc887aae42edba0662c7767054a40ac096d2@gmail.com>

greenplum-db/gpdb,lisakowen/gpdb,adam8157/gpdb,adam8157/gpdb,ashwinstar/gpdb,lisakowen/gpdb,techdragon/Postgres-XL,lisakowen/gpdb,jmcatamney/gpdb,adam8157/gpdb,Postgres-XL/Postgres-XL,xinzweb/gpdb,yazun/postgres-xl,oberstet/postgres-xl,techdragon/Postgres-XL,ovr/postgres-xl,greenplum-db/gpdb,xinzweb/gpdb,Postgres-XL/Postgres-XL,greenplum-db/gpdb,zeroae/postgres-xl,techdragon/Postgres-XL,lisakowen/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,lisakowen/gpdb,ashwinstar/gpdb,adam8157/gpdb,ovr/postgres-xl,adam8157/gpdb,50wu/gpdb,zeroae/postgres-xl,xinzweb/gpdb,ovr/postgres-xl,ashwinstar/gpdb,jmcatamney/gpdb,zeroae/postgres-xl,xinzweb/gpdb,xinzweb/gpdb,yazun/postgres-xl,50wu/gpdb,xinzweb/gpdb,zeroae/postgres-xl,techdragon/Postgres-XL,oberstet/postgres-xl,ovr/postgres-xl,oberstet/postgres-xl,greenplum-db/gpdb,xinzweb/gpdb,adam8157/gpdb,jmcatamney/gpdb,Postgres-XL/Postgres-XL,lisakowen/gpdb,50wu/gpdb,lisakowen/gpdb,pavanvd/postgres-xl,jmcatamney/gpdb,oberstet/postgres-xl,ovr/postgres-xl,jmcatamney/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,pavanvd/postgres-xl,Postgres-XL/Postgres-XL,oberstet/postgres-xl,yazun/postgres-xl,greenplum-db/gpdb,zeroae/postgres-xl,50wu/gpdb,xinzweb/gpdb,jmcatamney/gpdb,50wu/gpdb,ashwinstar/gpdb,pavanvd/postgres-xl,yazun/postgres-xl,50wu/gpdb,50wu/gpdb,Postgres-XL/Postgres-XL,50wu/gpdb,adam8157/gpdb,lisakowen/gpdb,ashwinstar/gpdb,adam8157/gpdb,pavanvd/postgres-xl,yazun/postgres-xl,pavanvd/postgres-xl,techdragon/Postgres-XL