[PATCH] Fix debug fallout of proposed PR68162 fix

[Richard Biener <rguenther@suse.de>]

The following patch makes sure we still emit a DW_TAG_typedef for
the element typedef in gcc.dg/debug/dwarf2/pr47939-4.c after a change
to how the C frontend structures the variant chain of arrays.

It makes dwarf2out _not_ re-build the variant for arrays (like it
does for vectors).

Patch was tested by Joseph (also on gdb testsuite?) and I'm currently
re-testing on x86_64-unknown-linux-gnu.

Ok for trunk and GCC 5 branch?

Thanks,
Richard.

2015-11-18  Richard Biener  <rguenther@suse.de>

	PR c/68162
	* dwarf2out.c (gen_type_die_with_usage): Keep variant types
	of arrays.

Index: gcc/dwarf2out.c
===================================================================
--- gcc/dwarf2out.c	(revision 230428)
+++ gcc/dwarf2out.c	(working copy)
@@ -20784,9 +20784,10 @@ gen_type_die_with_usage (tree type, dw_d
   /* We are going to output a DIE to represent the unqualified version
      of this type (i.e. without any const or volatile qualifiers) so
      get the main variant (i.e. the unqualified version) of this type
-     now.  (Vectors are special because the debugging info is in the
+     now.  (Vectors and arrays are special because the debugging info is in the
      cloned type itself).  */
-  if (TREE_CODE (type) != VECTOR_TYPE)
+  if (TREE_CODE (type) != VECTOR_TYPE
+      && TREE_CODE (type) != ARRAY_TYPE)
     type = type_main_variant (type);
 
   /* If this is an array type with hidden descriptor, handle it first.  */