diff --git a/tests/unit_tests/crypto.cpp b/tests/unit_tests/crypto.cpp
index 29fa88f9d..e09ec7f7a 100644
--- a/tests/unit_tests/crypto.cpp
+++ b/tests/unit_tests/crypto.cpp
@@ -47,6 +47,9 @@ namespace
     "8b655970153799af2aeadc9ff1add0ea6c7251d54154cfa92c173a0dd39c1f94"
     "6c7251d54154cfa92c173a0dd39c1f948b655970153799af2aeadc9ff1add0ea";
 
+  template<typename T> void *addressof(T &t) { return &t; }
+  template<> void *addressof(crypto::secret_key &k) { return addressof(unwrap(unwrap(k))); }
+
   template<typename T>
   bool is_formatted()
   {
@@ -55,7 +58,7 @@ namespace
     static_assert(alignof(T) == 1, "T must have 1 byte alignment");
     static_assert(sizeof(T) <= sizeof(source), "T is too large for source");
     static_assert(sizeof(T) * 2 <= sizeof(expected), "T is too large for destination");
-    std::memcpy(std::addressof(value), source, sizeof(T));
+    std::memcpy(addressof(value), source, sizeof(T));
 
     std::stringstream out;
     out << "BEGIN" << value << "END";