* c-lex.c (lex_string): Let cpp_parse_escape handles truncation
and sign-extension.
(lex_charconst): Update for change in prototype of
cpp_interpret_charconst. Extend from cppchar_t to HOST_WIDE_INT
appropriately.
* cpphash.h (BITS_PER_CPPCHAR_T): New.
* cppinit.c (cpp_create_reader): Initialize them for no
change in semantics.
(cpp_post_options): Add sanity checks.
* cpplex.c (cpp_parse_escape): Handle precision, sign-extension
and truncation issues. Calculate in type cppchar_t.
(MAX_CHAR_TYPE_SIZE, MAX_WCHAR_TYPE_SIZE): Remove.
(cpp_interpret_charconst): Calculate in type cppchar_t. Handle
run-time dependent precision correctly. Return whether the
result is signed or not.
* cpplib.c (dequote_string): Use cppchar_t; update.
* cpplib.h (cppchar_signed_t): New.
struct cpp_options): New precision members.
(cpp_interpret_charconst, cpp_parse_escape): Update prototypes.
From-SVN: r53152
