diff --git a/ChangeLog b/ChangeLog
index 6794634f3c..f0a85f4f09 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri Nov 25 07:46:09 2011  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
+
+	* configure.in: add -Wall always.
+
 Thu Nov 24 20:02:40 2011  Tanaka Akira  <akr@fsij.org>
 
 	* test/openssl/test_engine.rb: use IO#reopen to restore stderr.
diff --git a/configure.in b/configure.in
index b3d9bd3e7d..af0b89145e 100644
--- a/configure.in
+++ b/configure.in
@@ -488,7 +488,7 @@ if test "$GCC:${warnflags+set}:no" = yes::no; then
 	    ])
 	])
     done
-    AS_CASE([" $warnflags "],[*" -Wno-missing-field-initializers "*], [wflag=-Wextra],
+    AS_CASE([" $warnflags "],[*" -Wno-missing-field-initializers "*], [wflag="-Wall -Wextra"],
                              [wflag=-Wall])
     RUBY_TRY_CFLAGS($wflag, [warnflags="$wflag${warnflags+ $warnflags}"])
     # Disable warnflags while conftest. -Werror=* flags might make bad OS capability guess.