diff --git a/ChangeLog b/ChangeLog
index 7a6b089975..ef4f7f8b61 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Jun 23 13:30:30 2011  Shota Fukumori  <sorah@tubusu.net>
+
+	* signal.c(ruby_atomic_exchange): Fix definement style.
+
 Wed Jun 22 22:34:05 2011  Hiroshi Nakamura  <nahi@ruby-lang.org>
 
 	* ext/openssl/ossl_ssl.c (ossl_sslctx_session_new_cb): Return 0 to
diff --git a/signal.c b/signal.c
index 8f251befb8..2e9f4f5aff 100644
--- a/signal.c
+++ b/signal.c
@@ -19,7 +19,8 @@
 #include "atomic.h"
 
 #if !defined(_WIN32) && !defined(HAVE_GCC_ATOMIC_BUILTINS)
-rb_atomic_t ruby_atomic_exchange(rb_atomic_t *ptr, rb_atomic_t val)
+rb_atomic_t
+ruby_atomic_exchange(rb_atomic_t *ptr, rb_atomic_t val)
 {
     rb_atomic_t old = *ptr;
     *ptr = val;