Enhance -Waddress to detect more suspicious expressions [PR102103].

Enhance -Waddress to detect more suspicious expressions [PR102103].

Resolves:
PR c/102103 - missing warning comparing array address to null

gcc/ChangeLog:

	PR c/102103
	* doc/invoke.texi (-Waddress): Update.
	* gengtype.c (write_types): Avoid -Waddress.
	* poly-int.h (POLY_SET_COEFF): Avoid using null.

gcc/c-family/ChangeLog:

	PR c/102103
	* c-common.c (decl_with_nonnull_addr_p): Handle members.
	Check and perform warning suppression.
	(c_common_truthvalue_conversion): Enhance warning suppression.

gcc/c/ChangeLog:

	PR c/102103
	* c-typeck.c (maybe_warn_for_null_address): New function.
	(build_binary_op): Call it.

gcc/cp/ChangeLog:

	PR c/102103
	* typeck.c (warn_for_null_address): Enhance.
	(cp_build_binary_op): Call it also for member pointers.

gcc/fortran/ChangeLog:

	PR c/102103
	* array.c: Remove an unnecessary test.
	* trans-array.c: Same.

gcc/testsuite/ChangeLog:

	PR c/102103
	* g++.dg/cpp0x/constexpr-array-ptr10.C: Suppress a valid warning.
	* g++.dg/warn/Wreturn-local-addr-6.C: Correct a cast.
	* gcc.dg/Waddress.c: Expect a warning.
	* c-c++-common/Waddress-3.c: New test.
	* c-c++-common/Waddress-4.c: New test.
	* g++.dg/warn/Waddress-5.C: New test.
	* g++.dg/warn/Waddress-6.C: New test.
	* g++.dg/warn/pr101219.C: Expect a warning.
	* gcc.dg/Waddress-3.c: New test.