diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 1b691fb05e0..9818d2750f8 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -485,7 +485,7 @@ pgfdw_exec_query(PGconn *conn, const char *query)
  *
  * This function offers quick responsiveness by checking for any interruptions.
  *
- * This function emulates the PQexec()'s behavior of returning the last result
+ * This function emulates PQexec()'s behavior of returning the last result
  * when there are many.
  *
  * Caller is responsible for the error handling on the result.
@@ -493,40 +493,50 @@ pgfdw_exec_query(PGconn *conn, const char *query)
 PGresult *
 pgfdw_get_result(PGconn *conn, const char *query)
 {
-	PGresult   *last_res = NULL;
+	PGresult   *volatile last_res = NULL;
 
-	for (;;)
+	/* In what follows, do not leak any PGresults on an error. */
+	PG_TRY();
 	{
-		PGresult   *res;
-
-		while (PQisBusy(conn))
+		for (;;)
 		{
-			int			wc;
+			PGresult   *res;
 
-			/* Sleep until there's something to do */
-			wc = WaitLatchOrSocket(MyLatch,
-								   WL_LATCH_SET | WL_SOCKET_READABLE,
-								   PQsocket(conn),
-								   -1L, PG_WAIT_EXTENSION);
-			ResetLatch(MyLatch);
-
-			CHECK_FOR_INTERRUPTS();
-
-			/* Data available in socket */
-			if (wc & WL_SOCKET_READABLE)
+			while (PQisBusy(conn))
 			{
-				if (!PQconsumeInput(conn))
-					pgfdw_report_error(ERROR, NULL, conn, false, query);
+				int			wc;
+
+				/* Sleep until there's something to do */
+				wc = WaitLatchOrSocket(MyLatch,
+									   WL_LATCH_SET | WL_SOCKET_READABLE,
+									   PQsocket(conn),
+									   -1L, PG_WAIT_EXTENSION);
+				ResetLatch(MyLatch);
+
+				CHECK_FOR_INTERRUPTS();
+
+				/* Data available in socket? */
+				if (wc & WL_SOCKET_READABLE)
+				{
+					if (!PQconsumeInput(conn))
+						pgfdw_report_error(ERROR, NULL, conn, false, query);
+				}
 			}
+
+			res = PQgetResult(conn);
+			if (res == NULL)
+				break;			/* query is complete */
+
+			PQclear(last_res);
+			last_res = res;
 		}
-
-		res = PQgetResult(conn);
-		if (res == NULL)
-			break;				/* query is complete */
-
-		PQclear(last_res);
-		last_res = res;
 	}
+	PG_CATCH();
+	{
+		PQclear(last_res);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
 	return last_res;
 }
@@ -1006,6 +1016,7 @@ pgfdw_exec_cleanup_query(PGconn *conn, const char *query, bool ignore_errors)
 		pgfdw_report_error(WARNING, result, conn, true, query);
 		return ignore_errors;
 	}
+	PQclear(result);
 
 	return true;
 }
@@ -1028,56 +1039,75 @@ pgfdw_exec_cleanup_query(PGconn *conn, const char *query, bool ignore_errors)
 static bool
 pgfdw_get_cleanup_result(PGconn *conn, TimestampTz endtime, PGresult **result)
 {
-	PGresult   *last_res = NULL;
+	volatile bool timed_out = false;
+	PGresult   *volatile last_res = NULL;
 
-	for (;;)
+	/* In what follows, do not leak any PGresults on an error. */
+	PG_TRY();
 	{
-		PGresult   *res;
-
-		while (PQisBusy(conn))
+		for (;;)
 		{
-			int			wc;
-			TimestampTz now = GetCurrentTimestamp();
-			long		secs;
-			int			microsecs;
-			long		cur_timeout;
+			PGresult   *res;
 
-			/* If timeout has expired, give up, else get sleep time. */
-			if (now >= endtime)
-				return true;
-			TimestampDifference(now, endtime, &secs, &microsecs);
-
-			/* To protect against clock skew, limit sleep to one minute. */
-			cur_timeout = Min(60000, secs * USECS_PER_SEC + microsecs);
-
-			/* Sleep until there's something to do */
-			wc = WaitLatchOrSocket(MyLatch,
-							  WL_LATCH_SET | WL_SOCKET_READABLE | WL_TIMEOUT,
-								   PQsocket(conn),
-								   cur_timeout, PG_WAIT_EXTENSION);
-			ResetLatch(MyLatch);
-
-			CHECK_FOR_INTERRUPTS();
-
-			/* Data available in socket */
-			if (wc & WL_SOCKET_READABLE)
+			while (PQisBusy(conn))
 			{
-				if (!PQconsumeInput(conn))
+				int			wc;
+				TimestampTz now = GetCurrentTimestamp();
+				long		secs;
+				int			microsecs;
+				long		cur_timeout;
+
+				/* If timeout has expired, give up, else get sleep time. */
+				if (now >= endtime)
 				{
-					*result = NULL;
-					return false;
+					timed_out = true;
+					goto exit;
+				}
+				TimestampDifference(now, endtime, &secs, &microsecs);
+
+				/* To protect against clock skew, limit sleep to one minute. */
+				cur_timeout = Min(60000, secs * USECS_PER_SEC + microsecs);
+
+				/* Sleep until there's something to do */
+				wc = WaitLatchOrSocket(MyLatch,
+							  WL_LATCH_SET | WL_SOCKET_READABLE | WL_TIMEOUT,
+									   PQsocket(conn),
+									   cur_timeout, PG_WAIT_EXTENSION);
+				ResetLatch(MyLatch);
+
+				CHECK_FOR_INTERRUPTS();
+
+				/* Data available in socket? */
+				if (wc & WL_SOCKET_READABLE)
+				{
+					if (!PQconsumeInput(conn))
+					{
+						/* connection trouble; treat the same as a timeout */
+						timed_out = true;
+						goto exit;
+					}
 				}
 			}
+
+			res = PQgetResult(conn);
+			if (res == NULL)
+				break;			/* query is complete */
+
+			PQclear(last_res);
+			last_res = res;
 		}
-
-		res = PQgetResult(conn);
-		if (res == NULL)
-			break;				/* query is complete */
-
-		PQclear(last_res);
-		last_res = res;
+exit:	;
 	}
+	PG_CATCH();
+	{
+		PQclear(last_res);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	*result = last_res;
-	return false;
+	if (timed_out)
+		PQclear(last_res);
+	else
+		*result = last_res;
+	return timed_out;
 }
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index 7509b4fe60a..f6fa0e4c16a 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -591,13 +591,19 @@ libpqrcv_PQexec(PGconn *streamConn, const char *query)
 				ResetLatch(MyLatch);
 				CHECK_FOR_INTERRUPTS();
 			}
+
+			/* Consume whatever data is available from the socket */
 			if (PQconsumeInput(streamConn) == 0)
-				return NULL;	/* trouble */
+			{
+				/* trouble; drop whatever we had and return NULL */
+				PQclear(lastResult);
+				return NULL;
+			}
 		}
 
 		/*
-		 * Emulate the PQexec()'s behavior of returning the last result when
-		 * there are many. We are fine with returning just last error message.
+		 * Emulate PQexec()'s behavior of returning the last result when there
+		 * are many.  We are fine with returning just last error message.
 		 */
 		result = PQgetResult(streamConn);
 		if (result == NULL)