re PR preprocessor/22168 (#if #A == #B should have a diagnostic in ISO C mode)

re PR preprocessor/22168 (#if #A == #B should have a diagnostic in ISO C mode)

libcpp
	PR preprocessor/22168:
	* include/cpplib.h (struct cpp_options) <objc>: Update
	documentation.
	* expr.c (eval_token): Warn for use of assertions.
	* directives.c (directive_diagnostics): Warn about extensions.
	(DEPRECATED): New define.
	(DIRECTIVE_TABLE): Use it.
gcc
	PR preprocessor/22168:
	* doc/cpp.texi (Top): Update menu.
	(Alternatives to Wrapper #ifndef): New node.
	(Other Directives): Document deprecation.
	(Obsolete Features): Remove menu.
	(Assertions): Merge node into Obsolete Features.
	(Obsolete once-only headers): Move earlier; rename to Alternatives
	to Wrapper #ifndef.
	* doc/cppopts.texi: Update.
	* c.opt (Wdeprecated): Enable for C and ObjC.
	* doc/invoke.texi (Option Summary): Move -Wno-deprecated.
	(C++ Dialect Options): Move -Wno-deprecated from here to...
	(Warning Options): ... here.
gcc/testsuite
	PR preprocessor/22168:
	* gcc.dg/pch/import-2.hs: Add -Wno-deprecated.
	* gcc.dg/pch/import-1.hs: Add -Wno-deprecated.
	* gcc.dg/pch/import-2.c: Add -Wno-deprecated.
	* gcc.dg/pch/import-1.c: Add -Wno-deprecated.
	* gcc.dg/cpp/import2.c: Add -Wno-deprecated.
	* gcc.dg/cpp/import1.c: Add -Wno-deprecated.
	* gcc.dg/cpp/trad/assert3.c: Add -Wno-deprecated.
	* gcc.dg/cpp/trad/assert2.c: Add -Wno-deprecated.
	* gcc.dg/cpp/trad/assert1.c: Add -Wno-deprecated.
	* gcc.dg/cpp/ident.c: Add -Wno-deprecated.
	* gcc.dg/cpp/ident-1.c: Add -Wno-deprecated.
	* gcc.dg/cpp/extratokens.c: Add -Wno-deprecated.
	* gcc.dg/cpp/assert3.c: Add -Wno-deprecated.
	* gcc.dg/cpp/assert2.c: Add -Wno-deprecated.
	* gcc.dg/cpp/assert1.c: Add -Wno-deprecated.
	* gcc.dg/cpp/assert4.c: Compile with -ansi and not -pedantic.  Add
	-Wno-deprecated.
	* gcc.dg/cpp/pr22168.c: New file.
	* gcc.dg/cpp/pr22168-2.c: New file.

From-SVN: r135264