* substring-locations.h (format_warning_va): Formatting fix for
	ATTRIBUTE_GCC_DIAG.
	(format_warning_at_substring): Fix up ATTRIBUTE_GCC_DIAG second
	argument.
	(format_warning_n_va, format_warning_at_substring_n): New prototypes.
	* substring-locations.c: Include intl.h.
	(format_warning_va): Turned into small wrapper around
	format_warning_n_va, renamed to ...
	(format_warning_n_va): ... this, add N and PLURAL_GMSGID arguments,
	rename GMSGID to SINGULAR_GMSGID, if SINGULAR_GMSGID != PLURAL_GMSGID,
	use ngettext.
	(format_warning_at_substring_n): New function.
	* gimple-ssa-sprintf.c: Remove GCC diagnostic ignored pragma.
	(fmtwarn): Add ATTRIBUTE_GCC_DIAG.  Turn into a copy of
	format_warning_at_substring with just a shorter name instead of
	const function pointer.
	(fmtwarn_n): New function.
	(maybe_warn, format_directive, parse_directive): Use fmtwarn_n where
	appropriate, get rid of all the fmtstr temporaries, move conditionals
	with G_() wrapped string literals directly into fmtwarn arguments,
	cast dir.len to (int), formatting fixes.

From-SVN: r258154