diff --git a/include/mruby/error.h b/include/mruby/error.h
--- a/include/mruby/error.h
+++ b/include/mruby/error.h
-/*
-** error.h - Exception class
-**
-** See Copyright Notice in mruby.h
-*/
-
-#ifndef MRUBY_ERROR_H
-#define MRUBY_ERROR_H
-
-#if defined(__cplusplus)
-extern "C" {
-#endif
-
-struct RException {
- MRB_OBJECT_HEADER;
- struct iv_tbl *iv;
- struct RString *mesg;
-};
-
-#define mrb_exc_ptr(v) ((struct RException*)mrb_ptr(v))
-#define MRB_EXC_MESG_STRING_FLAG 0x100
-
-void mrb_sys_fail(mrb_state *mrb, const char *mesg);
-mrb_value mrb_exc_new_str(mrb_state *mrb, struct RClass* c, mrb_value str);
-#define mrb_exc_new_str_lit(mrb, c, lit) mrb_exc_new_str(mrb, c, mrb_str_new_lit(mrb, lit))
-mrb_value mrb_make_exception(mrb_state *mrb, int argc, const mrb_value *argv);
-void mrb_exc_print(mrb_state *mrb, struct RObject *exc);
-void mrb_print_backtrace(mrb_state *mrb);
-mrb_value mrb_exc_backtrace(mrb_state *mrb, mrb_value exc);
-mrb_value mrb_get_backtrace(mrb_state *mrb);
-mrb_noreturn void mrb_no_method_error(mrb_state *mrb, mrb_sym id, mrb_int argc, const mrb_value *argv, const char *fmt, ...);
-
-/* declaration for fail method */
-mrb_value mrb_f_raise(mrb_state*, mrb_value);
-
-#if defined(__cplusplus)
-} /* extern "C" { */
-#endif
-
-#endif /* MRUBY_ERROR_H */
+/**
+** @file mruby/error.h - Exception class
+**
+** See Copyright Notice in mruby.h
+*/
+
+#ifndef MRUBY_ERROR_H
+#define MRUBY_ERROR_H
+
+#include "common.h"
+
+/**
+ * MRuby error handling.
+ */
+MRB_BEGIN_DECL
+
+struct RException {
+ MRB_OBJECT_HEADER;
+ struct iv_tbl *iv;
+ struct RString *mesg;
+};
+
+#define mrb_exc_ptr(v) ((struct RException*)mrb_ptr(v))
+#define MRB_EXC_MESG_STRING_FLAG 0x100
+
+MRB_API void mrb_sys_fail(mrb_state *mrb, const char *mesg);
+MRB_API mrb_value mrb_exc_new_str(mrb_state *mrb, struct RClass* c, mrb_value str);
+#define mrb_exc_new_lit(mrb, c, lit) mrb_exc_new_str(mrb, c, mrb_str_new_lit(mrb, lit))
+#define mrb_exc_new_str_lit(mrb, c, lit) mrb_exc_new_lit(mrb, c, lit)
+MRB_API mrb_value mrb_make_exception(mrb_state *mrb, mrb_int argc, const mrb_value *argv);
+mrb_value mrb_exc_backtrace(mrb_state *mrb, mrb_value exc);
+mrb_value mrb_get_backtrace(mrb_state *mrb);
+
+MRB_API mrb_noreturn void mrb_no_method_error(mrb_state *mrb, mrb_sym id, mrb_value args, const char *fmt, ...);
+
+/* declaration for `fail` method */
+MRB_API mrb_value mrb_f_raise(mrb_state*, mrb_value);
+
+#if defined(MRB_64BIT) || defined(MRB_USE_FLOAT32) || defined(MRB_NAN_BOXING) || defined(MRB_WORD_BOXING)
+struct RBreak {
+ MRB_OBJECT_HEADER;
+ const struct RProc *proc;
+ mrb_value val;
+};
+#define mrb_break_value_get(brk) ((brk)->val)
+#define mrb_break_value_set(brk, v) ((brk)->val = v)
+#else
+struct RBreak {
+ MRB_OBJECT_HEADER;
+ const struct RProc *proc;
+ union mrb_value_union value;
+};
+#define RBREAK_VALUE_TT_MASK ((1 << 8) - 1)
+static inline mrb_value
+mrb_break_value_get(struct RBreak *brk)
+{
+ mrb_value val;
+ val.value = brk->value;
+ val.tt = (enum mrb_vtype)(brk->flags & RBREAK_VALUE_TT_MASK);
+ return val;
+}
+static inline void
+mrb_break_value_set(struct RBreak *brk, mrb_value val)
+{
+ brk->value = val.value;
+ brk->flags &= ~RBREAK_VALUE_TT_MASK;
+ brk->flags |= val.tt;
+}
+#endif /* MRB_64BIT || MRB_USE_FLOAT32 || MRB_NAN_BOXING || MRB_WORD_BOXING */
+#define mrb_break_proc_get(brk) ((brk)->proc)
+#define mrb_break_proc_set(brk, p) ((brk)->proc = p)
+
+#define RBREAK_TAG_FOREACH(f) \
+ f(RBREAK_TAG_BREAK, 0) \
+ f(RBREAK_TAG_BREAK_UPPER, 1) \
+ f(RBREAK_TAG_BREAK_INTARGET, 2) \
+ f(RBREAK_TAG_RETURN_BLOCK, 3) \
+ f(RBREAK_TAG_RETURN, 4) \
+ f(RBREAK_TAG_RETURN_TOPLEVEL, 5) \
+ f(RBREAK_TAG_JUMP, 6) \
+ f(RBREAK_TAG_STOP, 7)
+
+#define RBREAK_TAG_DEFINE(tag, i) tag = i,
+enum {
+ RBREAK_TAG_FOREACH(RBREAK_TAG_DEFINE)
+};
+#undef RBREAK_TAG_DEFINE
+
+#define RBREAK_TAG_BIT 3
+#define RBREAK_TAG_BIT_OFF 8
+#define RBREAK_TAG_MASK (~(~UINT32_C(0) << RBREAK_TAG_BIT))
+
+static inline uint32_t
+mrb_break_tag_get(struct RBreak *brk)
+{
+ return (brk->flags >> RBREAK_TAG_BIT_OFF) & RBREAK_TAG_MASK;
+}
+
+static inline void
+mrb_break_tag_set(struct RBreak *brk, uint32_t tag)
+{
+ brk->flags &= ~(RBREAK_TAG_MASK << RBREAK_TAG_BIT_OFF);
+ brk->flags |= (tag & RBREAK_TAG_MASK) << RBREAK_TAG_BIT_OFF;
+}
+
+/**
+ * Protect
+ *
+ */
+typedef mrb_value mrb_protect_error_func(mrb_state *mrb, void *userdata);
+MRB_API mrb_value mrb_protect_error(mrb_state *mrb, mrb_protect_error_func *body, void *userdata, mrb_bool *error);
+
+/**
+ * Protect (takes mrb_value for body argument)
+ *
+ * Implemented in the mruby-error mrbgem
+ */
+MRB_API mrb_value mrb_protect(mrb_state *mrb, mrb_func_t body, mrb_value data, mrb_bool *state);
+
+/**
+ * Ensure
+ *
+ * Implemented in the mruby-error mrbgem
+ */
+MRB_API mrb_value mrb_ensure(mrb_state *mrb, mrb_func_t body, mrb_value b_data,
+ mrb_func_t ensure, mrb_value e_data);
+
+/**
+ * Rescue
+ *
+ * Implemented in the mruby-error mrbgem
+ */
+MRB_API mrb_value mrb_rescue(mrb_state *mrb, mrb_func_t body, mrb_value b_data,
+ mrb_func_t rescue, mrb_value r_data);
+
+/**
+ * Rescue exception
+ *
+ * Implemented in the mruby-error mrbgem
+ */
+MRB_API mrb_value mrb_rescue_exceptions(mrb_state *mrb, mrb_func_t body, mrb_value b_data,
+ mrb_func_t rescue, mrb_value r_data,
+ mrb_int len, struct RClass **classes);
+
+MRB_END_DECL
+
+#endif /* MRUBY_ERROR_H */