Fixed windows linking

.build_win32_amd64.txt

@@ -0,0 +1,4 @@
+1
+success
+542ffdc62c3efd2f659a1c14f3a15fe54c83e643
+06 Jul 2019 22:26:45

CMakeLists.txt

@@ -26,6 +26,19 @@ else()
 	set(SOURCE ${SOURCE} src/sha512.c)
 endif()
 
+if (MSVC)
+	set(CompilerFlags
+			CMAKE_CXX_FLAGS
+			CMAKE_CXX_FLAGS_DEBUG
+			CMAKE_CXX_FLAGS_RELEASE
+			CMAKE_C_FLAGS
+			CMAKE_C_FLAGS_DEBUG
+			CMAKE_C_FLAGS_RELEASE
+			)
+	foreach(CompilerFlag ${CompilerFlags})
+		string(REPLACE "/MD" "/MT" ${CompilerFlag} "${${CompilerFlag}}")
+	endforeach()
+endif()
 #Some programs need for full support the header files too
 set(HEADERS
 		include/ed25519.h

include/sha512.h

@@ -13,11 +13,20 @@ typedef struct sha512_functions_ {
 	int(*_ed_sha512_update)(sha512_context*, const unsigned char *, size_t);
 } sha512_functions;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #ifdef WIN32
 __declspec(dllexport)
 #endif
 extern sha512_functions _ed_sha512_functions;
 
+#ifdef __cplusplus
+}
+#endif
+
+
 inline void _ed_sha512_validate() {
     assert(_ed_sha512_functions._ed_sha512_init);
     assert(_ed_sha512_functions._ed_sha512_final);