Add pg_update C comment about problems with plpython_call_handler().

diff --git a/contrib/pg_upgrade/function.c b/contrib/pg_upgrade/function.c
index fe8fb408cd21c444073f2450652061d3c1d7cbf9..e38071ed95f5ced95eab0f3fd4a0d87bf8fba93d 100644 (file)
--- a/contrib/pg_upgrade/function.c
+++ b/contrib/pg_upgrade/function.c
@@ -240,6 +240,12 @@ check_loadable_libraries(void)
         *  For this case, we could check pg_pltemplate, but that only works
         *  for languages, and does not help with function shared objects,
         *  so we just do a general fix.
+        *
+        *  Some systems have plpython_call_handler() that references
+        *  "plpython" defined in the "public" schema, causing pg_dump to
+        *  dump it an generate an error on pg_dumpall restore;  not sure
+        *  on the cause, see:
+        *  http://archives.postgresql.org/pgsql-hackers/2012-03/msg01101.php
         */
        if (GET_MAJOR_VERSION(old_cluster.major_version) < 901 &&
            strcmp(lib, "$libdir/plpython") == 0)