introduce TDF_compare_debug, omit OBJ_TYPE_REF casts with it

for  gcc/ChangeLog

	* dumpfile.h (TDF_COMPARE_DEBUG): New.
	* final.c (rest_of_clean_state): Set it for the
	-fcompare-debug dump.
	* tree-pretty-print.c (dump_generic_node): Omit OBJ_TYPE_REF
	class when TDF_COMPARE_DEBUG is set.

From-SVN: r254751

1 files changed, 9 insertions, 1 deletions

diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index 61a28c6..80d45f9 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -2760,7 +2760,15 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
       pp_string (pp, "OBJ_TYPE_REF(");
       dump_generic_node (pp, OBJ_TYPE_REF_EXPR (node), spc, flags, false);
       pp_semicolon (pp);
-      if (!(flags & TDF_SLIM) && virtual_method_call_p (node))
+      /* We omit the class type for -fcompare-debug because we may
+	 drop TYPE_BINFO early depending on debug info, and then
+	 virtual_method_call_p would return false, whereas when
+	 TYPE_BINFO is preserved it may still return true and then
+	 we'd print the class type.  Compare tree and rtl dumps for
+	 libstdc++-prettyprinters/shared_ptr.cc with and without -g,
+	 for example, at occurrences of OBJ_TYPE_REF.  */
+      if (!(flags & (TDF_SLIM | TDF_COMPARE_DEBUG))
+	  && virtual_method_call_p (node))
 	{
 	  pp_string (pp, "(");
 	  dump_generic_node (pp, obj_type_ref_class (node), spc, flags, false);