[PATCH] Handle DW_TAG_subrange_type

[Andreas Schwab <schwab@suse.de>]

When trying to debug Ada code you often get a DW_TAG_subrange_type, which
gdb can't handle yet.

Andreas.

2003-11-22  Andreas Schwab  <schwab@suse.de>

	* dwarf2read.c (dwarf2_non_const_array_bound_ignored_complaint):
	New function.
	(read_subrange_type): New function.
	(process_die): Handle DW_TAG_subrange_type.
	(read_type_die): Likewise.

--- gdb/dwarf2read.c.~1.114.~	2003-11-21 12:51:28.000000000 +0100
+++ gdb/dwarf2read.c	2003-11-22 16:52:42.000000000 +0100
@@ -610,6 +610,13 @@ dwarf2_non_const_array_bound_ignored_com
 }
 
 static void
+dwarf2_non_const_subrange_bound_ignored_complaint (const char *arg1)
+{
+  complaint (&symfile_complaints, "non-constant subrange bounds form '%s' ignored",
+	     arg1);
+}
+
+static void
 dwarf2_statement_list_fits_in_line_number_section_complaint (void)
 {
   complaint (&symfile_complaints,
@@ -844,6 +851,8 @@ static void read_tag_string_type (struct
 
 static void read_subroutine_type (struct die_info *, struct dwarf2_cu *);
 
+static void read_subrange_type (struct die_info *, struct dwarf2_cu *);
+
 static struct die_info *read_comp_unit (char *, bfd *, struct dwarf2_cu *);
 
 static struct die_info *read_die_and_children (char *info_ptr, bfd *abfd,
@@ -1908,6 +1917,9 @@ process_die (struct die_info *die, struc
 	  new_symbol (die, die->type, cu);
 	}
       break;
+    case DW_TAG_subrange_type:
+      read_subrange_type (die, cu);
+      break;
     case DW_TAG_common_block:
       read_common_block (die, cu);
       break;
@@ -3732,6 +3744,72 @@ read_base_type (struct die_info *die, st
   die->type = type;
 }
 
+static void
+read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
+{
+  struct type *element_type;
+  struct attribute *attr;
+  unsigned int low, high;
+
+  /* Return if we've already decoded this type. */
+  if (die->type)
+    {
+      return;
+    }
+
+  element_type = die_type (die, cu);
+  low = 0;
+  high = -1;
+  if (cu_language == language_fortran)
+    {
+      /* FORTRAN implies a lower bound of 1, if not given.  */
+      low = 1;
+    }
+  attr = dwarf_attr (die, DW_AT_lower_bound);
+  if (attr)
+    {
+      if (attr->form == DW_FORM_sdata)
+	low = DW_SND (attr);
+      else if (attr->form == DW_FORM_udata
+	       || attr->form == DW_FORM_data1
+	       || attr->form == DW_FORM_data2
+	       || attr->form == DW_FORM_data4
+	       || attr->form == DW_FORM_data8)
+	{
+	  low = DW_UNSND (attr);
+	}
+      else
+	{
+	  dwarf2_non_const_subrange_bound_ignored_complaint
+	    (dwarf_form_name (attr->form));
+	  low = 0;
+	}
+    }
+  attr = dwarf_attr (die, DW_AT_upper_bound);
+  if (attr)
+    {
+      if (attr->form == DW_FORM_sdata)
+	{
+	  high = DW_SND (attr);
+	}
+      else if (attr->form == DW_FORM_udata
+	       || attr->form == DW_FORM_data1
+	       || attr->form == DW_FORM_data2
+	       || attr->form == DW_FORM_data4
+	       || attr->form == DW_FORM_data8)
+	{
+	  high = DW_UNSND (attr);
+	}
+      else
+	{
+	  dwarf2_non_const_subrange_bound_ignored_complaint
+	    (dwarf_form_name (attr->form));
+	  high = 1;
+	}
+    }
+  die->type = create_range_type (NULL, element_type, low, high);
+}
+
 /* Read a whole compilation unit into a linked list of dies.  */
 
 static struct die_info *
@@ -5674,6 +5752,9 @@ read_type_die (struct die_info *die, str
     case DW_TAG_base_type:
       read_base_type (die, cu);
       break;
+    case DW_TAG_subrange_type:
+      read_subrange_type (die, cu);
+      break;
     default:
       complaint (&symfile_complaints, "unexepected tag in read_type_die: '%s'",
 		 dwarf_tag_name (die->tag));

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Deutschherrnstr. 15-19, D-90429 Nürnberg
Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
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