Index: graphite-flattening.c
===================================================================
--- graphite-flattening.c	(revision 184683)
+++ graphite-flattening.c	(working copy)
@@ -454,6 +454,11 @@ lst_do_flatten (lst_p lst)
 bool
 flatten_all_loops (scop_p scop)
 {
+  /* Disable loop flattening, see PR50335.
+     As unfortunate as it is, this code is unmaintained
+     and may soon be removed.  */
+  if (1)
+    return false;
   return lst_do_flatten (SCOP_TRANSFORMED_SCHEDULE (scop));
 }