// -std=c++0x
class __FlashStringHelper;
-#define F(string_literal) (reinterpret_cast<__FlashStringHelper *>(PSTR(string_literal)))
+#define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))
// An inherited class for holding the result of a concatenation. These
// result objects are assumed to be writable by subsequent concatenations.