* cpperror.c (print_location): New function.
        (print_containing_files): Simplify.
        (_cpp_begin_message): Simplify and use print_location.
        * cppfiles.c (stack_include_file): Update.
        (_cpp_pop_file_buffer): Update.
        * cpphash.h (struct cpp_buffer): New members
        include_stack_listed and type.
        * cpplib.c (_cpp_handle_directive): Buffer->inc is not null.
        (run_directive): Take buffer type.  cpp_push_buffer cannot fail.
        (_cpp_do__Pragma, cpp_define, _cpp_define_builtin, cpp_undef,
        handle_assertion): Update.
        (cpp_push_buffer): Take a buffer type and file name.
        (cpp_pop_buffer): Update.  Clear include_stack_listed.
        * cpplib.h (input_stack_listing_current): Remove.
        (enum cpp_buffer_type): New.
        (cpp_push_buffer): New prototype.
        * cppmacro.c (builtin_macro): Simplify; buffer cannot be null.
        * fix-header.c (read_scan_file): Update.

From-SVN: r38186