* c-common.c (c_common_init): -Wtraditional also implies -Wlong-long.

	* cppinit.c (cpp_post_options): Likewise.

	* cppexp.c (cpp_classify_number): Suppress -Wtraditional
	warning about 'LL' suffix (but not 'ULL' etc) when
	-Wno-long-long is in effect.

	* cppmacro.c (_cpp_builtin_macro_text) [BT_TIME, BT_DATE]:
	Check for failing time()/localtime(), issue a warning, and
	make __TIME__ and __DATE__ expand to fallback strings.

	* doc/cpp.texi, doc/extend.texi: Document behavior of __DATE__
	and __TIME__ when the date and time cannot be determined.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@55969 138bc75d-0d04-0410-961f-82ee72b054a4