From b92c7933ebf8a09a97ca2419d253a0ac1acdca6f Mon Sep 17 00:00:00 2001
From: Mark Wielaard <mjw@redhat.com>
Date: Sun, 23 Mar 2014 12:05:16 +0100
Subject: [PATCH] PR debug/16063. Add DW_AT_type to DW_TAG_enumeration.

Add a new lang-hook that provides the underlying base type of an
ENUMERAL_TYPE. Including implementations for C and C++. Use this
enum_underlying_base_type lang-hook in dwarf2out.c to add a DW_AT_type
base type reference to a DW_TAG_enumeration.

gcc/
	* dwarf2out.c (gen_enumeration_type_die): Add DW_AT_type if
	enum_underlying_base_type defined and DWARF version > 3.
	* langhooks.h (struct lang_hooks_for_types): Add
	enum_underlying_base_type.
	* langhooks-def.h (LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): New define.
	(LANG_HOOKS_FOR_TYPES_INITIALIZER): Add new lang hook.

gcc/c-family/
	* c-common.c (c_enum_underlying_base_type): New function.
	* c-common.h (c_enum_underlying_base_type): Add declaration.

gcc/c/
	* c-objc-common.h (LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): Define.

gcc/cp/
	* cp-lang.c (cxx_enum_underlying_base_type): New function.
	(LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): Define.
---
 gcc/ChangeLog           |   10 ++++++++++
 gcc/c-family/ChangeLog  |    6 ++++++
 gcc/c-family/c-common.c |    8 ++++++++
 gcc/c-family/c-common.h |    1 +
 gcc/c/ChangeLog         |    5 +++++
 gcc/c/c-objc-common.h   |    2 ++
 gcc/cp/ChangeLog        |    6 ++++++
 gcc/cp/cp-lang.c        |   18 ++++++++++++++++++
 gcc/dwarf2out.c         |    7 +++++++
 gcc/langhooks-def.h     |    4 +++-
 gcc/langhooks.h         |    2 ++
 11 files changed, 68 insertions(+), 1 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b456eff..7bce951 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,15 @@
 2014-03-21  Mark Wielaard  <mjw@redhat.com>
 
+	PR debug/16063
+	* dwarf2out.c (gen_enumeration_type_die): Add DW_AT_type if
+	enum_underlying_base_type defined and DWARF version > 3.
+	* langhooks.h (struct lang_hooks_for_types): Add
+	enum_underlying_base_type.
+	* langhooks-def.h (LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): New define.
+	(LANG_HOOKS_FOR_TYPES_INITIALIZER): Add new lang hook.
+
+2014-03-21  Mark Wielaard  <mjw@redhat.com>
+
 	* dwarf2out.c (gen_enumeration_type_die): Add DW_AT_const_value
 	as unsigned or int depending on type and value used.
 
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 536b4fc..94d779d 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,9 @@
+2014-03-21  Mark Wielaard  <mjw@redhat.com>
+
+	PR debug/16063
+	* c-common.c (c_enum_underlying_base_type): New function.
+	* c-common.h (c_enum_underlying_base_type): Add declaration.
+
 2014-03-22  Jakub Jelinek  <jakub@redhat.com>
 
 	PR debug/60603
diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index abd96fb..55ebbcc 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -3902,6 +3902,14 @@ c_register_builtin_type (tree type, const char* name)
 
   registered_builtin_types = tree_cons (0, type, registered_builtin_types);
 }
+
+/* The C version of the enum_underlying_base_type langhook.  */
+tree
+c_enum_underlying_base_type (const_tree type)
+{
+  return c_common_type_for_size (TYPE_PRECISION (type), TYPE_UNSIGNED (type));
+}
+
 
 /* Print an error message for invalid operands to arith operation
    CODE with TYPE0 for operand 0, and TYPE1 for operand 1.
diff --git a/gcc/c-family/c-common.h b/gcc/c-family/c-common.h
index 1099b10..e378b44 100644
--- a/gcc/c-family/c-common.h
+++ b/gcc/c-family/c-common.h
@@ -832,6 +832,7 @@ extern void c_common_finish (void);
 extern void c_common_parse_file (void);
 extern alias_set_type c_common_get_alias_set (tree);
 extern void c_register_builtin_type (tree, const char*);
+extern tree c_enum_underlying_base_type (const_tree);
 extern bool c_promoting_integer_type_p (const_tree);
 extern int self_promoting_args_p (const_tree);
 extern tree strip_pointer_operator (tree);
diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index b39b7d6..9ab6eab 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,8 @@
+2014-03-21  Mark Wielaard  <mjw@redhat.com>
+
+	PR debug/16063
+	* c-objc-common.h (LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): Define.
+
 2014-03-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
 	PR c/55383
diff --git a/gcc/c/c-objc-common.h b/gcc/c/c-objc-common.h
index 92cf60f..0651db7 100644
--- a/gcc/c/c-objc-common.h
+++ b/gcc/c/c-objc-common.h
@@ -84,6 +84,8 @@ along with GCC; see the file COPYING3.  If not see
 #define LANG_HOOKS_TO_TARGET_CHARSET c_common_to_target_charset
 #undef LANG_HOOKS_EXPR_TO_DECL
 #define LANG_HOOKS_EXPR_TO_DECL c_expr_to_decl
+#undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
+#define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE c_enum_underlying_base_type
 
 /* The C front end's scoping structure is very different from
    that expected by the language-independent code; it is best
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 1acfec3..8dad776 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2014-03-21  Mark Wielaard  <mjw@redhat.com>
+
+	PR debug/16063
+	* cp-lang.c (cxx_enum_underlying_base_type): New function.
+	(LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): Define.
+
 2014-03-21  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/60384
diff --git a/gcc/cp/cp-lang.c b/gcc/cp/cp-lang.c
index c28c07a..6a40d29 100644
--- a/gcc/cp/cp-lang.c
+++ b/gcc/cp/cp-lang.c
@@ -23,6 +23,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "coretypes.h"
 #include "tm.h"
 #include "tree.h"
+#include "stor-layout.h"
 #include "cp-tree.h"
 #include "c-family/c-common.h"
 #include "langhooks.h"
@@ -40,6 +41,7 @@ static enum classify_record cp_classify_record (tree type);
 static tree cp_eh_personality (void);
 static tree get_template_innermost_arguments_folded (const_tree);
 static tree get_template_argument_pack_elems_folded (const_tree);
+static tree cxx_enum_underlying_base_type (const_tree);
 
 /* Lang hooks common to C++ and ObjC++ are declared in cp/cp-objcp-common.h;
    consequently, there should be very few hooks below.  */
@@ -81,6 +83,8 @@ static tree get_template_argument_pack_elems_folded (const_tree);
 #define LANG_HOOKS_EH_PERSONALITY cp_eh_personality
 #undef LANG_HOOKS_EH_RUNTIME_TYPE
 #define LANG_HOOKS_EH_RUNTIME_TYPE build_eh_type_type
+#undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
+#define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE cxx_enum_underlying_base_type
 
 /* Each front end provides its own lang hook initializer.  */
 struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
@@ -219,5 +223,19 @@ get_template_argument_pack_elems_folded (const_tree t)
   return fold_cplus_constants (get_template_argument_pack_elems (t));
 }
 
+/* The C++ version of the enum_underlying_base_type langhook.
+   See also cp/semantics.c (finish_underlying_type).  */
+static tree cxx_enum_underlying_base_type (const_tree type)
+{
+  tree underlying_type = ENUM_UNDERLYING_TYPE (type);
+
+  if (! ENUM_FIXED_UNDERLYING_TYPE_P (type))
+    underlying_type
+      = c_common_type_for_mode (TYPE_MODE (underlying_type),
+                                TYPE_UNSIGNED (underlying_type));
+
+  return underlying_type;
+}
+
 #include "gt-cp-cp-lang.h"
 #include "gtype-cp.h"
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index af97408..554f787 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -17339,6 +17339,13 @@ gen_enumeration_type_die (tree type, dw_die_ref context_die)
 
       TREE_ASM_WRITTEN (type) = 1;
       add_byte_size_attribute (type_die, type);
+      if (lang_hooks.types.enum_underlying_base_type != NULL
+	  && (dwarf_version >= 3 || !dwarf_strict))
+	{
+	  tree underlying = lang_hooks.types.enum_underlying_base_type (type);
+	  dw_die_ref underlying_die = base_type_die (underlying);
+	  add_AT_die_ref (type_die, DW_AT_type, underlying_die);
+	}
       if (TYPE_STUB_DECL (type) != NULL_TREE)
 	{
 	  add_src_coords_attributes (type_die, TYPE_STUB_DECL (type));
diff --git a/gcc/langhooks-def.h b/gcc/langhooks-def.h
index 95bd379..b8e0d97 100644
--- a/gcc/langhooks-def.h
+++ b/gcc/langhooks-def.h
@@ -173,6 +173,7 @@ extern tree lhd_make_node (enum tree_code);
 #define LANG_HOOKS_GET_SUBRANGE_BOUNDS	NULL
 #define LANG_HOOKS_DESCRIPTIVE_TYPE	NULL
 #define LANG_HOOKS_RECONSTRUCT_COMPLEX_TYPE reconstruct_complex_type
+#define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE NULL
 
 #define LANG_HOOKS_FOR_TYPES_INITIALIZER { \
   LANG_HOOKS_MAKE_TYPE, \
@@ -191,7 +192,8 @@ extern tree lhd_make_node (enum tree_code);
   LANG_HOOKS_GET_ARRAY_DESCR_INFO, \
   LANG_HOOKS_GET_SUBRANGE_BOUNDS, \
   LANG_HOOKS_DESCRIPTIVE_TYPE, \
-  LANG_HOOKS_RECONSTRUCT_COMPLEX_TYPE \
+  LANG_HOOKS_RECONSTRUCT_COMPLEX_TYPE, \
+  LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE \
 }
 
 /* Declaration hooks.  */
diff --git a/gcc/langhooks.h b/gcc/langhooks.h
index c848b0c..667298b 100644
--- a/gcc/langhooks.h
+++ b/gcc/langhooks.h
@@ -137,6 +137,8 @@ struct lang_hooks_for_types
      return values from functions.  The argument TYPE is the top of the
      chain, and BOTTOM is the new type which we will point to.  */
   tree (*reconstruct_complex_type) (tree, tree);
+
+  tree (*enum_underlying_base_type) (const_tree);
 };
 
 /* Language hooks related to decls and the symbol table.  */
-- 
1.7.1

