c.opt (-Wdate-time): New option

2013-11-05  Tobias Burnus  <burnus@net-b.de>

gcc/c-family/
        * c.opt (-Wdate-time): New option
        * c-opts.c (sanitize_cpp_opts): Pass on to libcpp.

gcc/
        * doc/invoke.texi (-Wdate-time): Document.

gcc/fortran
        * lang.opt (-Wdate-time): New option
        * cpp.c (gfc_cpp_option_data): Add warn_date_time.
        (gfc_cpp_init_options, gfc_cpp_handle_option,
        gfc_cpp_post_options): Handle it and pass on to libcpp.

gcc/testsuite/
        * g++.dg/warn/wdate-time.C: New.
        * gcc.dg/wdate-time.c: New.
        * gfortran.dg/wdate-time.F90: New.

libcpp/
        * include/cpplib.h (CPP_W_DATE_TIME): Added.
        (cpp_options): Add warn_date_time.
        * init.c (cpp_create_reader): Init it.
        * macro.c (_cpp_builtin_macro_text): Warn when
        __DATE__/__TIME__/__TIMESTAMP__ is used.

From-SVN: r204420