diff --git a/include/sha512.h b/include/sha512.h
index 7a79c6d..89a266c 100644
--- a/include/sha512.h
+++ b/include/sha512.h
@@ -12,6 +12,10 @@ typedef struct sha512_functions_ {
 	int(*_ed_sha512_final)(sha512_context*, unsigned char *);
 	int(*_ed_sha512_update)(sha512_context*, const unsigned char *, size_t);
 } sha512_functions;
+
+#ifdef WIN32
+__declspec(dllexport)
+#endif
 extern sha512_functions _ed_sha512_functions;
 
 inline void _ed_sha512_validate() {
diff --git a/src/sha512.c b/src/sha512.c
index 0d33ce8..7b4ec4d 100644
--- a/src/sha512.c
+++ b/src/sha512.c
@@ -283,6 +283,9 @@ int __ed_sha512_update(sha512_context *md, const unsigned char *in, size_t inlen
     return _ed_sha512_update(md->context, in, inlen);
 }
 
+#ifdef WIN32
+__declspec(dllexport)
+#endif
 sha512_functions _ed_sha512_functions = {
         __ed_sha512_init,
         __ed_sha512_final,
diff --git a/src/sha512_openssl.c b/src/sha512_openssl.c
index e4f0082..46d9d01 100644
--- a/src/sha512_openssl.c
+++ b/src/sha512_openssl.c
@@ -23,6 +23,10 @@ int _ed_sha512_update(sha512_context* md, const unsigned char *in, size_t inlen)
 	return SHA512_Update(md->context, in, inlen) != 1; /* Returns 0 on success */
 }
 
+
+#ifdef WIN32
+__declspec(dllexport)
+#endif
 sha512_functions _ed_sha512_functions = {
 		_ed_sha512_init,
 		_ed_sha512_final,