[PATCH] Interpret DW_TAG_unspecified_type as void

[Julian Brown <julian at codesourcery dot com>]

Hi,

This is part of a series of patches from a CodeSourcery branch which 
enable the output of ARM's RVCT 2.2 compiler to be debugged with gdb.

This patch handles the C/C++ interpretation of the DWARF 3 construct 
DW_TAG_unspecified_type as void. This is used in representing e.g. 
pointer-to-void types. Other languages will currently be handled in 
exactly the same way; though I'm not entirely sure if that's a sensible 
default, I don't know what would be better. (Re: section 5.2 of the 
DWARF 3 doc.)

Tested natively on x86_64-unknown-linux-gnu and cross to arm-none-eabi 
with no change in results. Tests against the ARM compiler are improved 
somewhat.

OK to apply?

Cheers,

Julian

ChangeLog (Daniel Jacobowitz):

    * dwarf2read.c (read_unspecified_type): New function.
    (read_type_die): Handle DW_TAG_unspecified_type.

Index: src/gdb/dwarf2read.c
===================================================================
--- src.orig/gdb/dwarf2read.c	2005-03-07 06:00:16.000000000 -0800
+++ src/gdb/dwarf2read.c	2005-03-07 07:27:38.000000000 -0800
@@ -4992,6 +4992,23 @@ read_subrange_type (struct die_info *die
   set_die_type (die, range_type, cu);
 }
   
+static void
+read_unspecified_type (struct die_info *die, struct dwarf2_cu *cu)
+{
+  struct type *type;
+  struct attribute *attr;
+
+  if (die->type)
+    return;
+
+  /* For now, we only support the C meaning of an unspecified type: void.  */
+
+  attr = dwarf2_attr (die, DW_AT_name, cu);
+  type = init_type (TYPE_CODE_VOID, 0, 0, attr ? DW_STRING (attr) : "",
+		    cu->objfile);
+
+  set_die_type (die, type, cu);
+}
 
 /* Read a whole compilation unit into a linked list of dies.  */
 
@@ -7526,6 +7543,9 @@ read_type_die (struct die_info *die, str
     case DW_TAG_base_type:
       read_base_type (die, cu);
       break;
+    case DW_TAG_unspecified_type:
+      read_unspecified_type (die, cu);
+      break;
     default:
       complaint (&symfile_complaints, _("unexepected tag in read_type_die: '%s'"),
 		 dwarf_tag_name (die->tag));