diff --git a/ChangeLog b/ChangeLog
index 15e9e1c7b5..752db52770 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Thu Oct 16 23:17:40 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* signal.c (rb_sigaltstack_size): double default size to get rid
+	  of heap corruption by alternate stack overflow in SEGV handler.
+	  typically happened at fprintf() in control_frame_dump().
+
 Thu Oct 16 22:43:12 2014  Tanaka Akira  <akr@fsij.org>
 
 	* vm_backtrace.c (id2str): Fix a variable name.
diff --git a/signal.c b/signal.c
index fd7ee1bc51..63c79ffcbd 100644
--- a/signal.c
+++ b/signal.c
@@ -535,7 +535,7 @@ int
 rb_sigaltstack_size(void)
 {
     /* XXX: BSD_vfprintf() uses >1500KiB stack and x86-64 need >5KiB stack. */
-    int size = 8192;
+    int size = 16*1024;
 
 #ifdef MINSIGSTKSZ
     if (size < MINSIGSTKSZ)