diff --git a/ChangeLog b/ChangeLog
index f59c13fa96..c472c3b5fd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat May  8 11:07:41 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/bigdecimal/bigdecimal.c (VpAlloc): ensure buf does not get
+	  collected.  based on a patch masaya tarui at [ruby-dev:41213].
+
 Sat May  8 10:03:39 2010  Tanaka Akira  <akr@fsij.org>
 
 	* ext/socket/lib/socket.rb (BasicSocket#connect_address): MacOS X 10.6
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index 9a3dec83d8..817fc13cfd 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -2593,7 +2593,7 @@ VpAlloc(U_LONG mx, const char *szVal)
     int  sign=1;
     Real *vp = NULL;
     U_LONG mf = VpGetPrecLimit();
-    volatile VALUE buf;
+    VALUE buf;
 
     mx = (mx + BASE_FIG - 1) / BASE_FIG + 1;    /* Determine allocation unit. */
     if(szVal) {
@@ -2621,7 +2621,7 @@ VpAlloc(U_LONG mx, const char *szVal)
 
     /* Skip all '_' after digit: 2006-6-30 */
     ni = 0;
-    buf = rb_str_new(0,strlen(szVal)+1);
+    buf = rb_str_tmp_new(strlen(szVal)+1);
     psz = RSTRING_PTR(buf);
     i   = 0;
     ipn = 0;
@@ -2720,6 +2720,7 @@ VpAlloc(U_LONG mx, const char *szVal)
     vp->MaxPrec = mx;        /* set max precision */
     VpSetZero(vp,sign);
     VpCtoV(vp, &(szVal[ipn]), ni, &(szVal[ipf]), nf, &(szVal[ipe]), ne);
+    rb_str_resize(buf, 0);
     return vp;
 }
 
diff --git a/test/bigdecimal/test_bigdecimal.rb b/test/bigdecimal/test_bigdecimal.rb
index b266233b20..b8d933eb1c 100644
--- a/test/bigdecimal/test_bigdecimal.rb
+++ b/test/bigdecimal/test_bigdecimal.rb
@@ -698,4 +698,15 @@ class TestBigDecimal < Test::Unit::TestCase
     assert_equal(BigDecimal::SIGN_POSITIVE_ZERO, BigDecimal.new("1E-1" + "0" * 10000).sign)
     assert_equal(BigDecimal::SIGN_NEGATIVE_ZERO, BigDecimal.new("-1E-1" + "0" * 10000).sign)
   end
+
+  def test_gc
+    bug3258 = '[ruby-dev:41213]'
+    stress, GC.stress = GC.stress, true
+    1000.times do |i|
+      b = BigDecimal.new("1"+"0"*i).to_s
+      assert_equal([1, "1", 10, i+1], b.split, bug3258)
+    end
+  ensure
+    GC.stress = stress
+  end
 end