diff --git a/src/block-sha1/sha1.c b/src/block-sha1/sha1.c
index b433410c8..e3409fb59 100644
--- a/src/block-sha1/sha1.c
+++ b/src/block-sha1/sha1.c
@@ -68,6 +68,7 @@
  */
 
 #if defined(__i386__) || defined(__x86_64__) || \
+    defined(_M_IX86) || defined(_M_X64) || \
     defined(__ppc__) || defined(__ppc64__) || \
     defined(__powerpc__) || defined(__powerpc64__) || \
     defined(__s390__) || defined(__s390x__)