diff --git a/Data/UnixTime/Types.hsc b/Data/UnixTime/Types.hsc
--- a/Data/UnixTime/Types.hsc
+++ b/Data/UnixTime/Types.hsc
@@ -12,8 +12,6 @@
 
 #include <sys/time.h>
 
-#let alignment t = "%lu", (unsigned long)offsetof(struct {char x__; t (y__); }, y__)
-
 -- |
 -- Data structure for Unix time.
 --
@@ -35,7 +33,7 @@
 
 instance Storable UnixTime where
     sizeOf _    = (#size struct timeval)
-    alignment _ = (#alignment struct timeval)
+    alignment _ = (#const offsetof(struct {char x__; struct timeval (y__); }, y__))
     peek ptr    = UnixTime
             <$> (#peek struct timeval, tv_sec)  ptr
             <*> (#peek struct timeval, tv_usec) ptr
diff --git a/unix-time.cabal b/unix-time.cabal
--- a/unix-time.cabal
+++ b/unix-time.cabal
@@ -1,5 +1,5 @@
 Name:                   unix-time
-Version:                0.3.5
+Version:                0.3.6
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3