Cast NULL to a pointer type in the execl() call, to avoid a compiler warning on some platforms and possibly a bug.  Per report from Stefan and subsequent discussion.
Cast NULL to a pointer type in the execl() call, to avoid a compiler warning on
some platforms and possibly a bug.  Per report from Stefan and subsequent
discussion.

Chibin/gpdb,rvs/gpdb,royc1/gpdb,Quikling/gpdb,arcivanov/postgres-xl,Quikling/gpdb,adam8157/gpdb,snaga/postgres-xl,0x0FFF/gpdb,kaknikhil/gpdb,pavanvd/postgres-xl,Chibin/gpdb,chrishajas/gpdb,tpostgres-projects/tPostgres,postmind-net/postgres-xl,janebeckman/gpdb,xuegang/gpdb,yuanzhao/gpdb,edespino/gpdb,ahachete/gpdb,greenplum-db/gpdb,Chibin/gpdb,cjcjameson/gpdb,rvs/gpdb,yuanzhao/gpdb,yazun/postgres-xl,royc1/gpdb,ashwinstar/gpdb,CraigHarris/gpdb,zaksoup/gpdb,techdragon/Postgres-XL,ahachete/gpdb,ahachete/gpdb,ashwinstar/gpdb,rvs/gpdb,CraigHarris/gpdb,xinzweb/gpdb,arcivanov/postgres-xl,CraigHarris/gpdb,zaksoup/gpdb,CraigHarris/gpdb,cjcjameson/gpdb,tpostgres-projects/tPostgres,techdragon/Postgres-XL,50wu/gpdb,Quikling/gpdb,Postgres-XL/Postgres-XL,yuanzhao/gpdb,postmind-net/postgres-xl,oberstet/postgres-xl,jmcatamney/gpdb,cjcjameson/gpdb,yazun/postgres-xl,tpostgres-projects/tPostgres,snaga/postgres-xl,postmind-net/postgres-xl,janebeckman/gpdb,50wu/gpdb,zaksoup/gpdb,janebeckman/gpdb,royc1/gpdb,rvs/gpdb,janebeckman/gpdb,arcivanov/postgres-xl,xuegang/gpdb,yuanzhao/gpdb,lisakowen/gpdb,kaknikhil/gpdb,CraigHarris/gpdb,Chibin/gpdb,yuanzhao/gpdb,cjcjameson/gpdb,snaga/postgres-xl,zeroae/postgres-xl,edespino/gpdb,zaksoup/gpdb,jmcatamney/gpdb,Quikling/gpdb,ashwinstar/gpdb,postmind-net/postgres-xl,tpostgres-projects/tPostgres,janebeckman/gpdb,zaksoup/gpdb,lisakowen/gpdb,yuanzhao/gpdb,rvs/gpdb,kaknikhil/gpdb,edespino/gpdb,kaknikhil/gpdb,cjcjameson/gpdb,pavanvd/postgres-xl,cjcjameson/gpdb,adam8157/gpdb,zaksoup/gpdb,arcivanov/postgres-xl,greenplum-db/gpdb,Quikling/gpdb,ashwinstar/gpdb,rvs/gpdb,xinzweb/gpdb,yuanzhao/gpdb,0x0FFF/gpdb,cjcjameson/gpdb,50wu/gpdb,kaknikhil/gpdb,adam8157/gpdb,Postgres-XL/Postgres-XL,chrishajas/gpdb,chrishajas/gpdb,greenplum-db/gpdb,royc1/gpdb,edespino/gpdb,lintzc/gpdb,Chibin/gpdb,kaknikhil/gpdb,xuegang/gpdb,greenplum-db/gpdb,greenplum-db/gpdb,xuegang/gpdb,yazun/postgres-xl,chrishajas/gpdb,pavanvd/postgres-xl,edespino/gpdb,Quikling/gpdb,xuegang/gpdb,royc1/gpdb,jmcatamney/gpdb,edespino/gpdb,techdragon/Postgres-XL,Chibin/gpdb,ashwinstar/gpdb,adam8157/gpdb,kaknikhil/gpdb,xuegang/gpdb,jmcatamney/gpdb,Chibin/gpdb,xuegang/gpdb,edespino/gpdb,cjcjameson/gpdb,snaga/postgres-xl,zeroae/postgres-xl,rvs/gpdb,Postgres-XL/Postgres-XL,lintzc/gpdb,jmcatamney/gpdb,lisakowen/gpdb,adam8157/gpdb,zeroae/postgres-xl,xinzweb/gpdb,pavanvd/postgres-xl,CraigHarris/gpdb,ahachete/gpdb,kaknikhil/gpdb,CraigHarris/gpdb,cjcjameson/gpdb,Quikling/gpdb,janebeckman/gpdb,0x0FFF/gpdb,techdragon/Postgres-XL,snaga/postgres-xl,50wu/gpdb,xuegang/gpdb,yuanzhao/gpdb,CraigHarris/gpdb,ahachete/gpdb,oberstet/postgres-xl,chrishajas/gpdb,zeroae/postgres-xl,lintzc/gpdb,zeroae/postgres-xl,50wu/gpdb,ashwinstar/gpdb,adam8157/gpdb,zaksoup/gpdb,ovr/postgres-xl,chrishajas/gpdb,Postgres-XL/Postgres-XL,Quikling/gpdb,rvs/gpdb,ovr/postgres-xl,arcivanov/postgres-xl,arcivanov/postgres-xl,50wu/gpdb,ovr/postgres-xl,xuegang/gpdb,cjcjameson/gpdb,postmind-net/postgres-xl,xinzweb/gpdb,0x0FFF/gpdb,janebeckman/gpdb,edespino/gpdb,ovr/postgres-xl,lintzc/gpdb,xinzweb/gpdb,greenplum-db/gpdb,adam8157/gpdb,chrishajas/gpdb,xinzweb/gpdb,royc1/gpdb,janebeckman/gpdb,ahachete/gpdb,lintzc/gpdb,zaksoup/gpdb,jmcatamney/gpdb,0x0FFF/gpdb,xinzweb/gpdb,lisakowen/gpdb,ahachete/gpdb,lintzc/gpdb,lintzc/gpdb,yuanzhao/gpdb,jmcatamney/gpdb,ahachete/gpdb,rvs/gpdb,kmjungersen/PostgresXL,rvs/gpdb,Quikling/gpdb,ashwinstar/gpdb,techdragon/Postgres-XL,Chibin/gpdb,lisakowen/gpdb,Chibin/gpdb,greenplum-db/gpdb,xinzweb/gpdb,kmjungersen/PostgresXL,chrishajas/gpdb,ovr/postgres-xl,lisakowen/gpdb,greenplum-db/gpdb,kmjungersen/PostgresXL,Quikling/gpdb,kaknikhil/gpdb,royc1/gpdb,yazun/postgres-xl,oberstet/postgres-xl,0x0FFF/gpdb,0x0FFF/gpdb,yazun/postgres-xl,jmcatamney/gpdb,yuanzhao/gpdb,ashwinstar/gpdb,Chibin/gpdb,edespino/gpdb,tpostgres-projects/tPostgres,lisakowen/gpdb,kmjungersen/PostgresXL,lintzc/gpdb,edespino/gpdb,pavanvd/postgres-xl,janebeckman/gpdb,0x0FFF/gpdb,oberstet/postgres-xl,adam8157/gpdb,janebeckman/gpdb,kmjungersen/PostgresXL,lintzc/gpdb,50wu/gpdb,lisakowen/gpdb,CraigHarris/gpdb,Postgres-XL/Postgres-XL,kaknikhil/gpdb,royc1/gpdb,oberstet/postgres-xl,50wu/gpdb