2 files changed, 16 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog
index 92f0401a6b..efc4976f21 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue May  7 12:07:35 2013  Tanaka Akira  <akr@fsij.org>
+
+	* pack.c (swap32): Don't redefine it if it is already defined.
+	  Bionic defines it.
+	  (swap64): Ditto.
+
 Mon May  6 20:50:37 2013  Tanaka Akira  <akr@fsij.org>
 
 	* ext/socket/socket.c (socket_s_ip_address_list): Fill sin6_scope_id
diff --git a/pack.c b/pack.c
index 1300e43b5d..644ffd947a 100644
--- a/pack.c
+++ b/pack.c
@@ -100,9 +100,16 @@ TOKEN_PASTE(swap,x)(xtype z)		\
     return r;				\
 }
 
-#if GCC_VERSION_SINCE(4,3,0)
-# define swap32(x) __builtin_bswap32(x)
-# define swap64(x) __builtin_bswap64(x)
+#ifndef swap32
+# if GCC_VERSION_SINCE(4,3,0)
+#  define swap32(x) __builtin_bswap32(x)
+# endif
+#endif
+
+#ifndef swap64
+# if GCC_VERSION_SINCE(4,3,0)
+#  define swap64(x) __builtin_bswap64(x)
+# endif
 #endif
 
 #ifndef swap16