PR middle-end/77671 - missing -Wformat-overflow warning on sprintf overflow with %s

PR middle-end/77671 - missing -Wformat-overflow warning on sprintf overflow with %s

gcc/ChangeLog:

	PR middle-end/77671
	* gimple-fold.c (gimple_fold_builtin_sprintf): Make extern.
	(gimple_fold_builtin_snprintf): Same.
	* gimple-fold.h (gimple_fold_builtin_sprintf): Declare.
	(gimple_fold_builtin_snprintf): Same.
	* gimple-ssa-sprintf.c (get_format_string): Correct the detection
	of character types.
	(is_call_safe): New function.
	(try_substitute_return_value): Call it.
	(try_simplify_call): New function.
	(pass_sprintf_length::handle_gimple_call): Call it.

gcc/testsuite/ChangeLog:

PR middle-end/77671
	* gcc.dg/tree-ssa/builtin-sprintf-7.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-8.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c: Adjust.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-2.c: Adjust.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-3.c: Adjust.

From-SVN: r248035