diff --git a/ChangeLog b/ChangeLog
index fd8829eb36..9bbdc62e75 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Sat Apr 14 12:55:03 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (UNREACHABLE): gcc 4.4 eliminates unreachable code
+	  if -O3 is given.
+
+	* win32/win32.c (child_result): dropped colon.
+
 Sat Apr 14 10:45:18 2012  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* lib/webrick/server.rb (WEBrick::GenericServer#start):
diff --git a/configure.in b/configure.in
index 9b44842666..e7cb7455a0 100644
--- a/configure.in
+++ b/configure.in
@@ -912,11 +912,13 @@ if test "$GCC" = yes; then
     fi
 
     AC_CACHE_CHECK(for __builtin_unreachable, rb_cv_func___builtin_unreachable,
+    [RUBY_WERROR_FLAG(
     [AC_TRY_LINK([@%:@include <stdlib.h>],
 	[exit(0); __builtin_unreachable();],
 	[rb_cv_func___builtin_unreachable=yes],
 	[rb_cv_func___builtin_unreachable=no])
     ])
+    ])
     if test "$rb_cv_func___builtin_unreachable" = yes; then
 	AC_DEFINE_UNQUOTED(UNREACHABLE, [__builtin_unreachable()])
     fi
diff --git a/win32/win32.c b/win32/win32.c
index 782cb61773..5437cb6c38 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -1079,7 +1079,7 @@ child_result(struct ChildRecord *child, int mode)
 	GetExitCodeProcess(child->hProcess, &exitcode);
 	CloseChildHandle(child);
 	_exit(exitcode);
-      default
+      default:
 	UNREACHABLE;
     }
 }