diff --git a/.gdbinit b/.gdbinit
index 3dbeff6a00..5f67324456 100644
--- a/.gdbinit
+++ b/.gdbinit
@@ -56,7 +56,20 @@ define rp
 	    ((struct RString*)$arg0)->as.heap.ptr : \
 	    ((struct RString*)$arg0)->as.ary)
     set print address on
-    printf " "
+    printf " encoding:%d ", ($flags & (RUBY_FL_USER8|RUBY_FL_USER9|RUBY_FL_USER10|RUBY_FL_USER11)) >> RUBY_ENCODING_SHIFT
+    if ($flags & (RUBY_FL_USER12|RUBY_FL_USER13)) == 0
+      printf "coderange:unknown "
+    else
+    if ($flags & (RUBY_FL_USER12|RUBY_FL_USER13)) == RUBY_FL_USER12
+      printf "coderange:single "
+    else
+    if ($flags & (RUBY_FL_USER12|RUBY_FL_USER13)) == RUBY_FL_USER13
+      printf "coderange:single "
+    else
+      printf "coderange:broken "
+    end
+    end
+    end
     print (struct RString *)$arg0
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_REGEXP
diff --git a/ChangeLog b/ChangeLog
index a8ed539d92..e0713814bc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue Oct 16 18:16:15 2007  Tanaka Akira  <akr@fsij.org>
+
+	* ruby.c (RUBY_ENCODING_SHIFT): added as enum.
+
+	* .gdbinit (rp): show encoding and coderange for strings.
+
 Tue Oct 16 14:48:38 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* parse.y (parser_regx_options): check if regexp encoding option
diff --git a/ruby.c b/ruby.c
index c39731385b..8c86ddfd47 100644
--- a/ruby.c
+++ b/ruby.c
@@ -59,6 +59,9 @@ static const union {
     enum ruby_special_consts	special_consts;
     enum ruby_value_type	value_type;
     enum node_type		node_type;
+    enum {
+        RUBY_ENCODING_SHIFT = ENCODING_SHIFT
+    } various;
 } dummy_gdb_enums;
 
 const VALUE RUBY_FL_MARK      = FL_MARK;