Makefile | 2 +-
 hash.h   | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 9d1d958bd..186ce17f2 100644
--- a/Makefile
+++ b/Makefile
@@ -1388,9 +1388,9 @@ ifdef APPLE_COMMON_CRYPTO
 endif
 
 ifdef USE_SHA1DC
-	SHA1_HEADER = "sha1dc/sha1.h"
 	LIB_OBJS += sha1dc/sha1.o
 	LIB_OBJS += sha1dc/ubc_check.o
+	BASIC_CFLAGS += -DSHA1DC
 else
 ifdef BLK_SHA1
 	LIB_OBJS += block-sha1/sha1.o
diff --git a/hash.h b/hash.h
index f0d9ddd0c..b7f4f1fd8 100644
--- a/hash.h
+++ b/hash.h
@@ -7,6 +7,8 @@
 #include <CommonCrypto/CommonDigest.h>
 #elif defined(SHA1_OPENSSL)
 #include <openssl/sha.h>
+#elif defined(SHA1DC)
+#include "sha1dc/sha1.h"
 #else /* SHA1_BLK */
 #include "block-sha1/sha1.h"
 #endif