diff --git a/xbyak/xbyak.h b/xbyak/xbyak.h
index 6ab93a0..dfe6274 100644
--- a/xbyak/xbyak.h
+++ b/xbyak/xbyak.h
@@ -614,16 +614,16 @@
 };
 struct RegRip {
 	sint64 disp_;
-	Label* label_;
+	const Label* label_;
 	bool isAddr_;
-	explicit RegRip(sint64 disp = 0, Label* label = 0, bool isAddr = false) : disp_(disp), label_(label), isAddr_(isAddr) {}
+	explicit RegRip(sint64 disp = 0, const Label* label = 0, bool isAddr = false) : disp_(disp), label_(label), isAddr_(isAddr) {}
 	friend const RegRip operator+(const RegRip& r, sint64 disp) {
 		return RegRip(r.disp_ + disp, r.label_, r.isAddr_);
 	}
 	friend const RegRip operator-(const RegRip& r, sint64 disp) {
 		return RegRip(r.disp_ - disp, r.label_, r.isAddr_);
 	}
-	friend const RegRip operator+(const RegRip& r, Label& label) {
+	friend const RegRip operator+(const RegRip& r, const Label& label) {
 		if (r.label_ || r.isAddr_) throw Error(ERR_BAD_ADDRESSING);
 		return RegRip(r.disp_, &label);
 	}