diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 384c9b6..385d18b 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -574,7 +574,7 @@ StartReplication(StartReplicationCmd *cmd)
 			 * to find the requested WAL segment in pg_xlog.
 			 *
 			 * XXX: we could be more strict here and only allow a startpoint
-			 * that's older than the switchpoint, if it it's still in the same
+			 * that's older than the switchpoint, if it's still in the same
 			 * WAL segment.
 			 */
 			if (!XLogRecPtrIsInvalid(switchpoint) &&
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
index 89b22f2..c6c90fb 100644
--- a/src/bin/pg_basebackup/receivelog.c
+++ b/src/bin/pg_basebackup/receivelog.c
@@ -753,7 +753,7 @@ ReadEndOfStreamingResult(PGresult *res, XLogRecPtr *startpos, uint32 *timeline)
  * initiating streaming with the START_STREAMING command.
  *
  * If the COPY ends (not necessarily successfully) due a message from the
- * server, returns a PGresult and sets sets *stoppos to the last byte written.
+ * server, returns a PGresult and sets *stoppos to the last byte written.
  * On any other sort of error, returns NULL.
  */
 static PGresult *
diff --git a/src/interfaces/ecpg/pgtypeslib/timestamp.c b/src/interfaces/ecpg/pgtypeslib/timestamp.c
index b0f9bf1..cf1fed2 100644
--- a/src/interfaces/ecpg/pgtypeslib/timestamp.c
+++ b/src/interfaces/ecpg/pgtypeslib/timestamp.c
@@ -419,7 +419,7 @@ dttofmtasc_replace(timestamp * ts, date dDate, int dow, struct tm * tm,
 					replace_val.str_val = months[tm->tm_mon];
 					replace_type = PGTYPES_TYPE_STRING_CONSTANT;
 					break;
-					/* the full name name of the month */
+					/* the full name of the month */
 					/* XXX should be locale aware */
 				case 'B':
 					replace_val.str_val = pgtypes_date_months[tm->tm_mon];