diff --git a/uppsrc/Core/Convert.h b/uppsrc/Core/Convert.h
index e03524009..d64996b03 100644
--- a/uppsrc/Core/Convert.h
+++ b/uppsrc/Core/Convert.h
@@ -28,7 +28,7 @@ public:
 	Convert();
 	virtual ~Convert();
 #else
-	#ifdef __clang__
+	#if defined(__clang__) || GCC_VERSION >= 40600
 	Convert(){};
 	#endif
 	virtual ~Convert() {}
diff --git a/uppsrc/Core/Core.h b/uppsrc/Core/Core.h
index ae4c0a57d..230ef888c 100644
--- a/uppsrc/Core/Core.h
+++ b/uppsrc/Core/Core.h
@@ -37,6 +37,7 @@
 #include "config.h"
 
 #include <typeinfo>
+#include <stddef.h>
 #include <math.h>
 #include <limits.h>
 #include <stdlib.h>
diff --git a/uppsrc/Core/config.h b/uppsrc/Core/config.h
index 7e7938b20..0b5b6691b 100644
--- a/uppsrc/Core/config.h
+++ b/uppsrc/Core/config.h
@@ -1,6 +1,10 @@
 #if __GNUC__
 
 	#define COMPILER_GCC 1
+
+	#define GCC_VERSION (__GNUC__ * 10000 \
+		               + __GNUC_MINOR__ * 100 \
+		               + __GNUC_PATCHLEVEL__)	
 	
 	#if __WIN32
 		#define COMPILER_MINGW