PR c++/87541 - ICE using a constant decl as an attribute alloc_size argument
PR c++/87542 - bogus error on attribute format with a named constant argument

gcc/ChangeLog:

	PR c++/87541
	PR c++/87542
	* tree.c (type_argument_type): New function.
	* tree.h (type_argument_type): Declare it.
	* gcc/doc/extend.texi (alloc_align): Update and clarify.
	(alloc_size, nonnull, sentinel): Same.

gcc/c-family/ChangeLog:

	PR c++/87541
	PR c++/87542
	* c-attribs.c (positional_argument): New function.
	(handle_alloc_size_attribute): Use it and simplify.
	(handle_alloc_align_attribute): Same.
	(handle_assume_aligned_attribute): Same.
	(handle_nonnull_attribute): Same.
	* c-common.c (check_function_arguments): Pass fntype to
	check_function_format.
	* c-common.h (check_function_format): Add an argument.
	(PosArgFlags, positional_argument): Declare new type and function.
	* c-format.c (decode_format_attr): Add arguments.
	(check_format_string, get_constant): Same.
	(convert_format_name_to_system_name): Adjust.

gcc/testsuite/ChangeLog:

	PR c++/87541
	PR c++/87542
	* g++.dg/ext/attr-alloc_size.C: New test.
	* c-c++-common/pr71574.c: Adjust diagnostics.
	* c-c++-common/attributes-1.c: Same.
	* gcc.dg/attr-alloc_align-2.c: Same.
	* gcc.dg/attr-alloc_align-4.c: New test.
	* gcc.dg/attr-alloc_size-2.c: Adjust diagnostics.
	* gcc.dg/attr-alloc_size.c: Same.
	* gcc.dg/attr-assume_aligned-4.c: New test.
	* gcc.dg/format/attr-3.c: Adjust diagnostics.
	* gcc.dg/nonnull-2.c: Same.
	* gcc.dg/torture/pr80612.c: Same.
	* obj-c++.dg/attributes/method-format-1.mm: Same.
	* obj-c++.dg/attributes/method-nonnull-1.mm: Same.
	* objc.dg/attributes/method-format-1.m: same.
	* objc.dg/attributes/method-nonnull-1.m: Same.

From-SVN: r266195