diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 67e2bcf3dfb..b1b0407fcc8 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,9 @@
+2011-10-18  Mikael Morin  <mikael@gcc.gnu.org>
+
+	PR fortran/50420
+	* trans-array.c (gfc_walk_array_ref): Allow zero rank arrays
+	if they are coarrays.
+
 2011-10-18  Mikael Morin  <mikael@gcc.gnu.org>
 
 	* trans-array.h (gfc_walk_array_ref): New prototype.
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index 89528b47239..3472804e4c6 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -7700,8 +7700,10 @@ gfc_walk_array_ref (gfc_ss * ss, gfc_expr * expr, gfc_ref * ref)
 		  gcc_unreachable ();
 		}
 	    }
-	  /* We should have at least one non-elemental dimension.  */
-	  gcc_assert (newss->data.info.dimen > 0);
+	  /* We should have at least one non-elemental dimension,
+	     unless we are creating a descriptor for a (scalar) coarray.  */
+	  gcc_assert (newss->data.info.dimen > 0
+		      || newss->data.info.ref->u.ar.as->corank > 0);
 	  ss = newss;
 	  break;