invoke.texi: Document -Wdiscarded-array-qualifiers.

invoke.texi: Document -Wdiscarded-array-qualifiers.

2014-12-20  Martin Uecker <uecker@eecs.berkeley.edu>

	* doc/invoke.texi: Document -Wdiscarded-array-qualifiers.
	* doc/extend.texi: Document new behavior for pointers to arrays
	with qualifiers.

c/
	* c-typeck.c: New behavious for pointers to arrays with qualifiers
        (common-pointer-type): For pointers to arrays take qualifiers from
	element type.
        (build_conditional_expr): Add warnings for lost qualifiers.
	(comp-target-types): Allow pointers to arrays with different qualifiers.
        (convert-for-assignment): Adapt warnings for discarded qualifiers. Add
	WARNING_FOR_QUALIFIERS macro and rename WARN_FOR_QUALIFIERS
        to PEDWARN_FOR_QUALIFIERS.

c-family/
	* c.opt (Wdiscarded-array-qualifiers): New option.

testsuite/
	* gcc.dg/Wwrite-strings-1.c: Change dg-warning.
	* gcc.dg/array-quals-1.c: Use -Wno-discarded-array-qualifiers.
	* gcc.dg/array-quals-2.c: Change dg-options, dg-warning.
	* gcc.dg/pointer-array-atomic.c: New test.
	* gcc.dg/pointer-array-quals-1.c: New test.
	* gcc.dg/pointer-array-quals-2.c: New test (-pedantic-errors).
	* gcc.dg/qual-component-1.c: Change dg-options, dg-warnings.

From-SVN: r218985