1 files changed, 4 insertions, 0 deletions
diff --git a/pack.c b/pack.c
index 780923f02b..848d9fdcae 100644
--- a/pack.c
+++ b/pack.c
@@ -78,7 +78,9 @@ TOKEN_PASTE(swap,x)(z)			\
     return r;				\
 }
 
+#ifndef swap16
 #define swap16(x)	((((x)&0xFF)<<8) | (((x)>>8)&0xFF))
+#endif
 #if SIZEOF_SHORT == 2
 #define swaps(x)	swap16(x)
 #else
@@ -92,10 +94,12 @@ define_swapx(s,short);
 #endif
 #endif
 
+#ifndef swap32
 #define swap32(x)	((((x)&0xFF)<<24)	\
 			|(((x)>>24)&0xFF)	\
 			|(((x)&0x0000FF00)<<8)	\
 			|(((x)&0x00FF0000)>>8)	)
+#endif
 #if SIZEOF_LONG == 4
 #define swapl(x)	swap32(x)
 #else