2 files changed, 10 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index 03a35aae9d..ca0278a838 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Fri Jul 15 19:11:00 2011  Kenta Murata  <mrkn@mrkn.jp>
+
+	* bignum.c (bigsub_int): add RB_GC_GUARD.  This patch is made by
+	  Makoto Kishimoto.  fixes #4223 [ruby-dev:42907]
+
+	* bignum.c (bigadd_int): ditto.
+
 Fri Jul 15 09:59:12 2011  Hiroshi Nakamura  <nahi@ruby-lang.org>
 
 	* backport r32546 from trunk.
diff --git a/bignum.c b/bignum.c
index 809b164ff7..9c289f7a8e 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1767,6 +1767,7 @@ bigsub_int(VALUE x, long y0)
     if (xn == 1 && num < 0) {
 	RBIGNUM_SET_SIGN(z, !RBIGNUM_SIGN(x));
 	zds[0] = (BDIGIT)-num;
+	RB_GC_GUARD(x);
 	return bignorm(z);
     }
     zds[0] = BIGLO(num);
@@ -1793,6 +1794,7 @@ bigsub_int(VALUE x, long y0)
     if (num < 0) {
 	z = bigsub(x, rb_int2big(y0));
     }
+    RB_GC_GUARD(x);
     return bignorm(z);
 }
 
@@ -1845,6 +1847,7 @@ bigadd_int(VALUE x, long y)
     while (i < zn) {
 	zds[i++] = 0;
     }
+    RB_GC_GUARD(x);
     return bignorm(z);
 }