diff --git a/src/util/json/Writer.cpp b/src/util/json/Writer.cpp
index de58649..3f174a6 100644
--- a/src/util/json/Writer.cpp
+++ b/src/util/json/Writer.cpp
@@ -87,7 +87,7 @@ void Writer::val(int v) {
 }
 
 // _____________________________________________________________________________
-void Writer::val(size_t v) {
+void Writer::val(uint64_t v) {
   valCheck();
   *_out << v;
 }
diff --git a/src/util/json/Writer.h b/src/util/json/Writer.h
index 72958fe..8ba5a48 100644
--- a/src/util/json/Writer.h
+++ b/src/util/json/Writer.h
@@ -72,8 +72,8 @@ class Writer {
   void val(const std::string& v);
   void val(const char* v);
   void val(double v);
-  void val(size_t v);
   void val(int v);
+  void val(uint64_t v);
   void val(bool v);
   void val(Null);
   void val(const Val& v);
diff --git a/src/util/tests/TestMain.cpp b/src/util/tests/TestMain.cpp
index 31d7cf1..330038e 100644
--- a/src/util/tests/TestMain.cpp
+++ b/src/util/tests/TestMain.cpp
@@ -3,6 +3,7 @@
 //
 
 #include <string>
+#include <clocale>
 #include "util/Misc.h"
 #include "util/Nullable.h"
 #include "util/String.h"