diff --git a/uppsrc/Core/Value.hpp b/uppsrc/Core/Value.hpp
index 1d32ffb9f..053c886e8 100644
--- a/uppsrc/Core/Value.hpp
+++ b/uppsrc/Core/Value.hpp
@@ -204,9 +204,9 @@ T& Value::GetSmall() const
 	ASSERT(t < 255);
 	if(Is((byte)t))
 		return GetSmallRaw<T>();
-	throw ValueTypeError(String().Cat() << "Invalid value conversion: "
-	                     << GetName() << " -> " << typeid(T).name(),
-	                     *this, t);
+	String h = String() << "Invalid value conversion: "
+	                    << GetName() << " -> " << typeid(T).name();
+	throw ValueTypeError(h, *this, t);
 	return *(T*)&data; // Silence compiler warning
 }
 
diff --git a/uppsrc/Core/config.h b/uppsrc/Core/config.h
index 60272d9e4..740c5c0da 100644
--- a/uppsrc/Core/config.h
+++ b/uppsrc/Core/config.h
@@ -1,3 +1,6 @@
+#ifndef CORE_CONFIG_H // sometimes we want just these fancy platform macros from this file...
+#define CORE_CONFIG_H
+
 #include <uppconfig.h>
 
 #if __GNUC__
@@ -153,3 +156,5 @@
 #if _MSC_VER >= 1900 // MSC from VS2015 is good enough C++11 compiler...
 #define CPP_11
 #endif
+
+#endif