--- gdb-6.4/gdb/dwarf2read.c
+++ gdb-6.4/gdb/dwarf2read.c
@@ -838,7 +838,7 @@ static struct line_header *(dwarf_decode
 static void dwarf_decode_lines (struct line_header *, char *, bfd *,
 				struct dwarf2_cu *, struct partial_symtab *);
 
-static void dwarf2_start_subfile (char *, char *);
+static void dwarf2_start_subfile (char *, char *, char *);
 
 static struct symbol *new_symbol (struct die_info *, struct type *,
 				  struct dwarf2_cu *);
@@ -6474,13 +6474,11 @@ dwarf_decode_lines (struct line_header *
 	     directory and file name numbers in the statement program
 	     are 1-based.  */
           struct file_entry *fe = &lh->file_names[file - 1];
-          char *dir;
+          char *dir = NULL;
 
           if (fe->dir_index)
             dir = lh->include_dirs[fe->dir_index - 1];
-          else
-            dir = comp_dir;
-	  dwarf2_start_subfile (fe->name, dir);
+	  dwarf2_start_subfile (fe->name, dir, comp_dir);
 	}
 
       /* Decode the table.  */
@@ -6582,7 +6580,7 @@ dwarf_decode_lines (struct line_header *
                 else
                   dir = comp_dir;
                 if (!decode_for_pst_p)
-                  dwarf2_start_subfile (fe->name, dir);
+                  dwarf2_start_subfile (fe->name, dir, comp_dir);
               }
 	      break;
 	    case DW_LNS_set_column:
@@ -6662,7 +6660,8 @@ dwarf_decode_lines (struct line_header *
 
 /* Start a subfile for DWARF.  FILENAME is the name of the file and
    DIRNAME the name of the source directory which contains FILENAME
-   or NULL if not known.
+   or NULL if not known.  COMP_DIR is the value of DW_AT_comp_dir.  If
+   DIRNAME specifies a relative path, it is appended to COMP_DIR.
    This routine tries to keep line numbers from identical absolute and
    relative file names in a common subfile.
 
@@ -6681,8 +6680,19 @@ dwarf_decode_lines (struct line_header *
    subfile, so that `break /srcdir/list0.c:1' works as expected.  */
 
 static void
-dwarf2_start_subfile (char *filename, char *dirname)
+dwarf2_start_subfile (char *filename, char *dirname, char *comp_dir)
 {
+  struct cleanup *back_to = make_cleanup (null_cleanup, 0);
+
+  /* If we have a relative dirname, append it to comp_dir.  */
+  if (dirname != NULL && !IS_ABSOLUTE_PATH (dirname) && comp_dir != NULL)
+    {
+      dirname = concat (comp_dir, "/", dirname, NULL);
+      make_cleanup (xfree, dirname);
+    }
+  else if (dirname == NULL)
+    dirname = comp_dir;
+
   /* If the filename isn't absolute, try to match an existing subfile
      with the full pathname.  */
 
@@ -6690,19 +6700,20 @@ dwarf2_start_subfile (char *filename, ch
     {
       struct subfile *subfile;
       char *fullname = concat (dirname, "/", filename, (char *)NULL);
+      make_cleanup (xfree, fullname);
 
       for (subfile = subfiles; subfile; subfile = subfile->next)
 	{
 	  if (FILENAME_CMP (subfile->name, fullname) == 0)
 	    {
 	      current_subfile = subfile;
-	      xfree (fullname);
+	      do_cleanups (back_to);
 	      return;
 	    }
 	}
-      xfree (fullname);
     }
   start_subfile (filename, dirname);
+  do_cleanups (back_to);
 }
 
 static void