diff --git a/configure.ac b/configure.ac
index 0e0a9d2..d88281b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -22,9 +22,8 @@ case $host_os in
 		CFLAGS="$CFLAGS -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_POSIX_SOURCE -D_GNU_SOURCE"
 		;;
 	*openbsd*)
-		AC_DEFINE([HAVE_ATTRIBUTE__BOUNDED__], [1], [OpenBSD gcc has __bounded__])
-		AC_DEFINE([HAVE_ATTRIBUTE__WEAK_ALIAS], [1], [OpenBSD gcc has __weak_alias])
-		AC_DEFINE([HAVE_ATTRIBUTE__DEAD], [1], [OpenBSD gcc has __dead])
+		AC_DEFINE([HAVE_ATTRIBUTE__BOUNDED__], [1], [OpenBSD has __bounded__])
+		AC_DEFINE([HAVE_ATTRIBUTE__DEAD], [1], [OpenBSD has __dead])
 		HAVE_SENSORS=true
 		;;
 	*solaris*)
diff --git a/include/sha2.h b/include/sha2.h
index 293c14f..9fda715 100644
--- a/include/sha2.h
+++ b/include/sha2.h
@@ -9,6 +9,16 @@
 
 #include "sha2_openbsd.h"
 
+#define __weak_alias(alias,sym)
+
+#define SHA224Transform(a, b) SHA256Transform(a, b)
+#define SHA224Update(a, b, c) SHA256Update(a, b, c)
+#define SHA224Pad(a) SHA256Pad(a)
+
+#define SHA384Transform(a, b) SHA512Transform(a, b)
+#define SHA384Update(a, b, c) SHA512Update(a, b, c)
+#define SHA384Pad(a) SHA512Pad(a)
+
 #define SHA512_CTX SHA2_CTX
 #define SHA512_Init(ctx) SHA512Init(ctx)
 #define SHA512_Update(ctx, buf, len) SHA512Update(ctx, (void *)buf, len)
diff --git a/include/sys/types.h b/include/sys/types.h
index 3588e4d..248cf24 100644
--- a/include/sys/types.h
+++ b/include/sys/types.h
@@ -18,12 +18,6 @@
 #define __dead
 #endif
 
-#if !defined(HAVE_ATTRIBUTE__WEAK_ALIAS) && !defined(__weak_alias)
-#define __weak_alias(alias,sym) \
-    __asm__(".weak " __STRING(alias) " ; " \
-	    __STRING(alias) " = " __STRING(sym))
-#endif
-
 #if !defined(HAVE_ATTRIBUTE__BOUNDED__) && !defined(__bounded__)
 # define __bounded__(x, y, z)
 #endif