add DWARF 4 support

https://bugs.gentoo.org/400663
https://bugzilla.redhat.com/show_bug.cgi?id=707677

--- debugedit-5.3.5/debugedit.c	2011-10-11 05:37:49.000000000 +0200
+++ debugedit-5.3.5/debugedit.c	2012-01-25 01:27:23.487999039 +0100
@@ -70,6 +70,10 @@
 #include <rpmtag.h>
 
 #define DW_TAG_partial_unit 0x3c
+#define DW_FORM_sec_offset 0x17
+#define DW_FORM_exprloc 0x18
+#define DW_FORM_flag_present 0x19
+#define DW_FORM_ref_sig8 0x20
 
 char *base_dir = NULL;
 char *dest_dir = NULL;
@@ -246,6 +250,7 @@
 #define DEBUG_STR	8
 #define DEBUG_FRAME	9
 #define DEBUG_RANGES	10
+#define DEBUG_TYPES	11
     { ".debug_info", NULL, NULL, 0, 0, 0 },
     { ".debug_abbrev", NULL, NULL, 0, 0, 0 },
     { ".debug_line", NULL, NULL, 0, 0, 0 },
@@ -257,6 +262,7 @@
     { ".debug_str", NULL, NULL, 0, 0, 0 },
     { ".debug_frame", NULL, NULL, 0, 0, 0 },
     { ".debug_ranges", NULL, NULL, 0, 0, 0 },
+    { ".debug_types", NULL, NULL, 0, 0, 0 },
     { NULL, NULL, NULL, 0, 0, 0 }
   };
 
@@ -349,7 +355,8 @@
 		goto no_memory;
 	    }
 	  form = read_uleb128 (ptr);
-	  if (form == 2 || form > DW_FORM_indirect)
+	  if (form == 2
+	      || (form > DW_FORM_flag_present && form != DW_FORM_ref_sig8))
 	    {
 	      error (0, 0, "%s: Unknown DWARF DW_FORM_%d", dso->filename, form);
 	      htab_delete (h);
@@ -378,7 +385,6 @@
 canonicalize_path (const char *s, char *d)
 {
   char *rv = d;
-  const char *sroot;
   char *droot;
 
   if (IS_DIR_SEPARATOR (*s))
@@ -394,7 +400,6 @@
 	s++;
     }
   droot = d;
-  sroot = s;
 
   while (*s)
     {
@@ -513,7 +518,7 @@
     }
 
   value = read_16 (ptr);
-  if (value != 2 && value != 3)
+  if (value != 2 && value != 3 && value != 4)
     {
       error (0, 0, "%s: DWARF version %d unhandled", dso->filename,
 	     value);
@@ -529,8 +534,8 @@
       return 1;
     }
   
-  opcode_base = ptr[4];
-  ptr = dir = ptr + 4 + opcode_base;
+  opcode_base = ptr[4 + (value >= 4)];
+  ptr = dir = ptr + 4 + (value >= 4) + opcode_base;
   
   /* dir table: */
   value = 1;
@@ -758,7 +763,8 @@
 	{
 	  if (t->attr[i].attr == DW_AT_stmt_list)
 	    {
-	      if (form == DW_FORM_data4)
+	      if (form == DW_FORM_data4
+		  || form == DW_FORM_sec_offset)
 		{
 		  list_offs = do_read_32_relocated (ptr);
 		  found_list_offs = 1;
@@ -864,6 +870,8 @@
 	      else
 		ptr += 4;
 	      break;
+	    case DW_FORM_flag_present:
+	      break;
 	    case DW_FORM_addr:
 	      ptr += ptr_size;
 	      break;
@@ -878,10 +886,12 @@
 	      break;
 	    case DW_FORM_ref4:
 	    case DW_FORM_data4:
+	    case DW_FORM_sec_offset:
 	      ptr += 4;
 	      break;
 	    case DW_FORM_ref8:
 	    case DW_FORM_data8:
+	    case DW_FORM_ref_sig8:
 	      ptr += 8;
 	      break;
 	    case DW_FORM_sdata:
@@ -910,6 +920,7 @@
 	      form = DW_FORM_block1;
 	      break;
 	    case DW_FORM_block:
+	    case DW_FORM_exprloc:
 	      len = read_uleb128 (ptr);
 	      form = DW_FORM_block1;
 	      assert (len < UINT_MAX);
@@ -1213,7 +1224,7 @@
 		}
 	      
 	      cu_version = read_16 (ptr);
-	      if (cu_version != 2 && cu_version != 3)
+	      if (cu_version != 2 && cu_version != 3 && cu_version != 4)
 		{
 		  error (0, 0, "%s: DWARF version %d unhandled", dso->filename,
 			 cu_version);