* config.gcc (*-*-linux* | frv-*-*linux* | *-*-kfreebsd*-gnu |
	*-*-knetbsd*-gnu | *-*-gnu* | *-*-kopensolaris*-gnu): Use
	glibc-c.o in c_target_objs and cxx_target_objs.  Use t-glibc in
	tmake_file.  Set target_has_targetcm.
	(tilegx-*-linux*, tilepro-*-linux*): Append to c_target_objs and
	cxx_target_objs rather than overriding previous value.
	* config/glibc-c.c, config/t-glibc: New.
	* doc/tm.texi.in (TARGET_C_PREINCLUDE): New @hook.
	* doc/tm.texi: Regenerate.
	* hooks.c (hook_constcharptr_void_null): New.
	* hooks.h (hook_constcharptr_void_null): Declare.

gcc/c-family:
	* c-common.h (pch_cpp_save_state): Declare.
	* c-target.def (c_preinclude): New hook.
	* c-opts.c (done_preinclude): New.
	(push_command_line_include): Handle default preincluded header.
	(cb_file_change): Call pch_cpp_save_state when calling
	push_command_line_include.
	* c-pch.c (pch_ready_to_save_cpp_state, pch_cpp_state_saved)
	(pch_cpp_save_state): New.
	(pch_init): Call pch_cpp_save_state conditionally, instead of
	calling cpp_save_state.

gcc/testsuite:
	* gcc.dg/c99-predef-1.c: New test.
	* gcc.dg/cpp/cmdlne-dU-1.c, gcc.dg/cpp/cmdlne-dU-2.c,
	gcc.dg/cpp/cmdlne-dU-3.c, gcc.dg/cpp/cmdlne-dU-4.c,
	gcc.dg/cpp/cmdlne-dU-5.c, gcc.dg/cpp/cmdlne-dU-6.c,
	gcc.dg/cpp/cmdlne-dU-7.c, gcc.dg/cpp/cmdlne-dU-8.c,
	gcc.dg/cpp/cmdlne-dU-9.c, gcc.dg/cpp/cmdlne-dU-10.c,
	gcc.dg/cpp/cmdlne-dU-11.c, gcc.dg/cpp/cmdlne-dU-12.c,
	gcc.dg/cpp/cmdlne-dU-13.c, gcc.dg/cpp/cmdlne-dU-14.c,
	gcc.dg/cpp/cmdlne-dU-15.c, gcc.dg/cpp/cmdlne-dU-16.c,
	gcc.dg/cpp/cmdlne-dU-17.c, gcc.dg/cpp/cmdlne-dU-18.c,
	gcc.dg/cpp/cmdlne-dU-19.c, gcc.dg/cpp/cmdlne-dU-20.c,
	gcc.dg/cpp/cmdlne-dU-21.c, gcc.dg/cpp/cmdlne-dU-22.c,
	gcc.dg/cpp/mi5.c, gcc.dg/cpp/multiline.c: Add -nostdinc to
	dg-options.

libcpp:
	* files.c (struct _cpp_file): Add implicit_preinclude.
	(pch_open_file): Allow a previously opened implicitly included
	file.
	(_cpp_find_file): Add implicit_preinclude argument.  Free file and
	do not call open_file_failed if implicit_preinclude.  Store
	implicit_preinclude value.
	(_cpp_stack_include, _cpp_fake_include, _cpp_compare_file_date):
	Update calls to _cpp_find_file.
	(_cpp_stack_include): Handle IT_DEFAULT.
	(cpp_push_default_include): New.
	* include/cpplib.h (cpp_push_default_include): Declare.
	* init.c (cpp_read_main_file): Update call to _cpp_find_file.
	* internal.h (enum include_type): Add IT_DEFAULT.
	(_cpp_find_file): Update prototype.

From-SVN: r192715