gcc:
2016-11-23  Paolo Bonzini  <bonzini@gnu.org>

	* system.h (HAVE_DESIGNATED_INITIALIZERS,
	HAVE_DESIGNATED_UNION_INITIALIZERS): Do not use
	"defined" in macros.
	* doc/cpp.texi (Defined): Mention -Wexpansion-to-defined.
	* doc/cppopts.texi (Invocation): Document -Wexpansion-to-defined.
	* doc/invoke.texi (Warning Options): Document -Wexpansion-to-defined.

gcc/c-family:
2016-11-23  Paolo Bonzini  <bonzini@gnu.org>

	* c.opt (Wexpansion-to-defined): New.

gcc/testsuite:
2016-11-23  Paolo Bonzini  <bonzini@gnu.org>

	* gcc.dg/cpp/defined.c: Mark newly introduced warnings and
	adjust for warning->pedwarn change.
	* gcc.dg/cpp/defined-syshdr.c,
	gcc.dg/cpp/defined-Wexpansion-to-defined.c,
	gcc.dg/cpp/defined-Wextra-Wno-expansion-to-defined.c,
	gcc.dg/cpp/defined-Wextra.c,
	gcc.dg/cpp/defined-Wno-expansion-to-defined.c: New testcases.

libcpp:
2016-11-23  Paolo Bonzini  <bonzini@gnu.org>

	* include/cpplib.h (struct cpp_options): Add new member
	warn_expansion_to_defined.
	(CPP_W_EXPANSION_TO_DEFINED): New enum member.
	* expr.c (parse_defined): Warn for all uses of "defined"
	in macros, and tie warning to CPP_W_EXPANSION_TO_DEFINED.
	Make it a pedwarning instead of a warning.
	* system.h (HAVE_DESIGNATED_INITIALIZERS): Do not use
	"defined" in macros.

From-SVN: r242743