contrib/amcheck needs RecentGlobalXmin to be PGDLLIMPORT'ified.

tglsfdc · tglsfdc · commit 56018bf26eec · 2017-03-09T22:55:46.000-05:00
Per buildfarm.  Maybe some of the other xmin variables in snapmgr.h
ought to get this too, but for the moment I'm just interested in
un-breaking the buildfarm.
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h
@@ -58,7 +58,7 @@ extern bool FirstSnapshotSet;
 
 extern TransactionId TransactionXmin;
 extern TransactionId RecentXmin;
-extern TransactionId RecentGlobalXmin;
+extern PGDLLIMPORT TransactionId RecentGlobalXmin;
 extern TransactionId RecentGlobalDataXmin;
 
 extern Snapshot GetTransactionSnapshot(void);
