re PR preprocessor/53690 ([C++11] \u0000 and \U00000000 are wrongly encoded as U...

re PR preprocessor/53690 ([C++11] \u0000 and \U00000000 are wrongly encoded as U+0001.)

/libcpp
2015-07-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/53690
	* charset.c (_cpp_valid_ucn): Add cppchar_t * parameter and change
	return type to bool.  Fix encoding of \u0000 and \U00000000 in C++.
	(convert_ucn): Adjust call.
	* lex.c (forms_identifier_p): Likewise.
	* internal.h (_cpp_valid_ucn): Adjust declaration.

/gcc/testsuite
2015-07-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/53690
	* g++.dg/cpp/pr53690.C: New.

From-SVN: r225353