Updated with patches from antoyo and suggested changes from aclements. (

#79)

Add basic support for DWARF v5

Also fixes a few other minor issues.

Co-authored-by: Noah Lev <camelidcamel@gmail.com>

dwarf/cursor.cc

@@ -67,6 +67,12 @@ cursor::skip_initial_length()
         }
 }
 
+void
+cursor::skip_unit_type()
+{
+    pos += sizeof(sbyte);
+}
+
 section_offset
 cursor::offset()
 {

dwarf/dwarf.cc

@@ -273,12 +273,23 @@ compilation_unit::compilation_unit(const dwarf &file, section_offset offset)
         cursor sub(subsec);
         sub.skip_initial_length();
         uhalf version = sub.fixed<uhalf>();
-        if (version < 2 || version > 4)
+        (void)version;
+        if (version > 5)
                 throw format_error("unknown compilation unit version " + std::to_string(version));
         // .debug_abbrev-relative offset of this unit's abbrevs
-        section_offset debug_abbrev_offset = sub.offset();
-        ubyte address_size = sub.fixed<ubyte>();
-        subsec->addr_size = address_size;
+        section_offset debug_abbrev_offset;
+        if(version >= 5)
+        {
+            sub.skip_unit_type();
+            ubyte address_size = sub.fixed<ubyte>();
+            subsec->addr_size = address_size;
+            debug_abbrev_offset = sub.offset();
+        }
+        else {
+            debug_abbrev_offset = sub.offset();
+            ubyte address_size = sub.fixed<ubyte>();
+            subsec->addr_size = address_size;
+        }
 
         m = make_shared<impl>(file, offset, subsec, debug_abbrev_offset,
                               sub.get_section_offset());

dwarf/internal.hh

@@ -178,6 +178,7 @@ struct cursor
         }
 
         void skip_initial_length();
+        void skip_unit_type();
         void skip_form(DW_FORM form);
 
         cursor &operator+=(section_offset offset)

dwarf/line.cc

@@ -84,7 +84,7 @@ line_table::line_table(const shared_ptr<section> &sec, section_offset offset,
         m->program_offset = cur.get_section_offset() + header_length;
         m->minimum_instruction_length = cur.fixed<ubyte>();
         m->maximum_operations_per_instruction = 1;
-        if (version == 4)
+        if (version >= 4)
                 m->maximum_operations_per_instruction = cur.fixed<ubyte>();
         if (m->maximum_operations_per_instruction == 0)
                 throw format_error("maximum_operations_per_instruction cannot"

elf/data.hh

@@ -553,7 +553,7 @@ struct Sym<Elf64, Order>
                 return (stb)(info >> 4);
         }
 
-        void set_binding(stb v) const
+        void set_binding(stb v)
         {
                 info = (info & 0xF) | ((unsigned char)v << 4);
         }