Fixes #511: Can now construct errors with fully-overriden what() me…

…ssage

src/cuda/api/error.hpp

@@ -290,6 +290,17 @@ class runtime_error : public ::std::runtime_error {
 	runtime_error(status::named_t error_code, ::std::string&& what_arg) :
 		runtime_error(static_cast<status_t>(error_code), what_arg) { }
 
+protected:
+	runtime_error(status_t error_code, ::std::runtime_error&& err) :
+		::std::runtime_error(::std::move(err)), code_(error_code)
+	{ }
+
+public:
+	static runtime_error with_message_override(status_t error_code, ::std::string complete_what_arg)
+	{
+		return runtime_error(error_code, ::std::runtime_error(::std::move(complete_what_arg)));
+	}
+
 	/**
 	 * Obtain the CUDA status code which resulted in this error being thrown.
 	 */

src/cuda/rtc/error.hpp

@@ -128,8 +128,8 @@ class runtime_error : public ::std::runtime_error {
 		code_(error_code)
 	{ }
 	// I wonder if I should do this the other way around
-	runtime_error(status_t<Kind> error_code, const ::std::string& what_arg) :
-		::std::runtime_error(what_arg + ": " + describe(error_code)),
+	runtime_error(status_t<Kind> error_code, ::std::string what_arg) :
+		::std::runtime_error(::std::move(what_arg) + ": " + describe(error_code)),
 		code_(error_code)
 	{ }
 	///@endcond
@@ -138,6 +138,17 @@ class runtime_error : public ::std::runtime_error {
 	runtime_error(status::named_t<Kind> error_code, const ::std::string& what_arg) :
 		runtime_error(static_cast<status_t<Kind>>(error_code), what_arg) { }
 
+protected:
+	runtime_error(status_t<Kind> error_code, ::std::runtime_error err) :
+		::std::runtime_error(::std::move(err)), code_(error_code)
+	{ }
+
+public:
+	static runtime_error with_message_override(status_t<Kind> error_code, ::std::string complete_what_arg)
+	{
+		return runtime_error<Kind>(error_code, ::std::runtime_error(complete_what_arg));
+	}
+
 	/**
 	 * Obtain the CUDA status code which resulted in this error being thrown.
 	 */
@@ -147,6 +158,7 @@ class runtime_error : public ::std::runtime_error {
 	status_t<Kind> code_;
 };
 
+
 } // namespace rtc
 
 // TODO: The following could use ::std::optional arguments - which would