4 files changed, 12 insertions, 19 deletions
diff --git a/src/codegen.c b/src/codegen.c
index c869285d9..a36d609c6 100644
--- a/src/codegen.c
+++ b/src/codegen.c
@@ -16,7 +16,7 @@
 #include "mruby/debug.h"
 #include "node.h"
 #include "opcode.h"
-#include "re.h"
+#include "mruby/re.h"
 #include "mrb_throw.h"
 
 typedef mrb_ast_node node;
diff --git a/src/error.c b/src/error.c
index feec9dbc5..feaa61122 100644
--- a/src/error.c
+++ b/src/error.c
@@ -127,7 +127,12 @@ exc_inspect(mrb_state *mrb, mrb_value exc)
   mesg = mrb_attr_get(mrb, exc, mrb_intern_lit(mrb, "mesg"));
   file = mrb_attr_get(mrb, exc, mrb_intern_lit(mrb, "file"));
   line = mrb_attr_get(mrb, exc, mrb_intern_lit(mrb, "line"));
-  append_mesg = !mrb_nil_p(mesg) && RSTRING_LEN(mesg) > 0;
+
+  append_mesg = !mrb_nil_p(mesg);
+  if (append_mesg) {
+    mesg = mrb_obj_as_string(mrb, mesg);
+    append_mesg = RSTRING_LEN(mesg) > 0;
+  }
 
   if (!mrb_nil_p(file) && !mrb_nil_p(line)) {
     str = mrb_str_dup(mrb, file);
@@ -144,14 +149,14 @@ exc_inspect(mrb_state *mrb, mrb_value exc)
     }
   }
   else {
-    str = mrb_str_new_cstr(mrb, mrb_obj_classname(mrb, exc));
+    const char *cname = mrb_obj_classname(mrb, exc);
+    str = mrb_str_new_cstr(mrb, cname);
+    mrb_str_cat_lit(mrb, str, ": ");
     if (append_mesg) {
-      mrb_str_cat_lit(mrb, str, ": ");
       mrb_str_append(mrb, str, mesg);
     }
     else {
-      mrb_str_cat_lit(mrb, str, ": ");
-      mrb_str_cat_cstr(mrb, str, mrb_obj_classname(mrb, exc));
+      mrb_str_cat_cstr(mrb, str, cname);
     }
   }
   return str;
diff --git a/src/re.h b/src/re.h
deleted file mode 100644
index ee2638b22..000000000
--- a/src/re.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/*
-** re.h - Regexp class
-**
-** See Copyright Notice in mruby.h
-*/
-
-#ifndef RE_H
-#define RE_H
-
-#define REGEXP_CLASS          "Regexp"
-
-#endif  /* RE_H */
diff --git a/src/string.c b/src/string.c
index ebc579ec5..9c206157e 100644
--- a/src/string.c
+++ b/src/string.c
@@ -14,7 +14,7 @@
 #include "mruby/class.h"
 #include "mruby/range.h"
 #include "mruby/string.h"
-#include "re.h"
+#include "mruby/re.h"
 
 #define STR_EMBED_P(s) ((s)->flags & MRB_STR_EMBED)
 #define STR_SET_EMBED_FLAG(s) ((s)->flags |= MRB_STR_EMBED)