re PR c++/69628 (Conditional jump or move depends on uninitialised value(s) in lex_charconst(cpp_token const*) (c-lex.c:1252))

	PR c++/69628
	* charset.c (cpp_interpret_charconst): Clear *PCHARS_SEEN
	and *UNSIGNEDP if bailing out early due to errors.

	* g++.dg/parse/pr69628.C: New test.

From-SVN: r233186