PR tree-optimization/88993 - GCC 9 -Wformat-overflow=2 should reflect real libc limits
PR tree-optimization/88835 - overly aggressive -Werror=format-overflow for printf

gcc/ChangeLog:

	PR tree-optimization/88993
	PR tree-optimization/88853
	* gimple-ssa-sprintf.c (sprintf_dom_walker::call_info::is_file_func):
	New helper.
	(sprintf_dom_walker::call_info::is_string_func): New helper.
	(format_directive): Only issue "may exceed" 4095/INT_MAX warnings
	for formatted string functions.
	(sprintf_dom_walker::handle_gimple_call): Fix a typo in a comment.

gcc/testsuite/ChangeLog:

	PR tree-optimization/88993
	PR tree-optimization/88853
	* gcc.dg/tree-ssa/builtin-fprintf-warn-2.c: New test.
	* gcc.dg/tree-ssa/builtin-printf-warn-2.c: New test.
	* gcc.dg/tree-ssa/builtin-snprintf-warn-3.c: Adjust.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-18.c: Same.

From-SVN: r269125