diff --git a/ChangeLog b/ChangeLog
index 43c81b0f33..38e593e101 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Mar 10 22:28:15 2011  Tanaka Akira  <akr@fsij.org>
+
+	* ext/openssl/ossl_ssl.h: parenthesize macro arguments.
+
 Thu Mar 10 21:59:37 2011  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* parse.y (parser_encode_length): add exception as UTF8-MAC for
diff --git a/ext/openssl/ossl_ssl.h b/ext/openssl/ossl_ssl.h
index 92df5f5599..034762fc46 100644
--- a/ext/openssl/ossl_ssl.h
+++ b/ext/openssl/ossl_ssl.h
@@ -12,15 +12,15 @@
 #define _OSSL_SSL_H_
 
 #define GetSSLSession(obj, sess) do { \
-	Data_Get_Struct(obj, SSL_SESSION, sess); \
-	if (!sess) { \
+	Data_Get_Struct((obj), SSL_SESSION, (sess)); \
+	if (!(sess)) { \
 		ossl_raise(rb_eRuntimeError, "SSL Session wasn't initialized."); \
 	} \
 } while (0)
 
 #define SafeGetSSLSession(obj, sess) do { \
-	OSSL_Check_Kind(obj, cSSLSession); \
-	GetSSLSession(obj, sess); \
+	OSSL_Check_Kind((obj), cSSLSession); \
+	GetSSLSession((obj), (sess)); \
 } while (0)
 
 extern VALUE mSSL;