diff --git a/debug_win32.cpp b/debug_win32.cpp
index 63a8ff58..f36f2802 100644
--- a/debug_win32.cpp
+++ b/debug_win32.cpp
@@ -17,6 +17,7 @@
 #include "./debug.hpp"
 
 #include "./except.hpp"
+#include "./log.hpp"
 
 #include <windows.h>
 
diff --git a/log.hpp b/log.hpp
index 505df6d3..9005772d 100644
--- a/log.hpp
+++ b/log.hpp
@@ -62,7 +62,7 @@ namespace util {
     void log (level_t, const std::string &msg);
 
     template <typename ...tail>
-    void log (level_t, const std::string &format, tail ..._tail);
+    void log (level_t, const std::string &format, tail&& ..._tail);
 
 
     //-------------------------------------------------------------------------
diff --git a/log.ipp b/log.ipp
index 2ddd311e..6afa260f 100644
--- a/log.ipp
+++ b/log.ipp
@@ -26,7 +26,7 @@
 namespace util {
     template <typename ...tail>
     void
-    log (level_t l, const std::string &format, tail ..._tail)
+    log (level_t l, const std::string &format, tail&& ..._tail)
     {
         log (l, format::render (format, std::forward<tail> (_tail)...));
     }