PR middle-end/49905 - Better sanity checking on sprintf src & dest to

gcc/ChangeLog:

	PR middle-end/49905
	* Makefile.in (OBJS): Add gimple-ssa-sprintf.o.
	* config/linux.h (TARGET_PRINTF_POINTER_FORMAT): Redefine.
	* config/linux.c (gnu_libc_printf_pointer_format): New function.
	* config/sol2.h (TARGET_PRINTF_POINTER_FORMAT): Same.
	* config/sol2.c (solaris_printf_pointer_format): New function.
	* doc/invoke.texi (-Wformat-length, -fprintf-return-value): New
	options.
	* doc/tm.texi.in (TARGET_PRINTF_POINTER_FORMAT): Document.
	* doc/tm.texi: Regenerate.
	* gimple-fold.h (get_range_strlen): New function.
	(get_maxval_strlen): Declare existing function.
	* gimple-fold.c (get_range_strlen): Add arguments and compute both
	maximum and minimum.
	 (get_range_strlen): Define overload.
	(get_maxval_strlen): Adjust.
	* gimple-ssa-sprintf.c: New file and pass.
	* passes.def (pass_sprintf_length): Add new pass.
	* targhooks.h (default_printf_pointer_format): Declare new function.
	(gnu_libc_printf_pointer_format): Same.
	(solaris_libc_printf_pointer_format): Same.
	* targhooks.c (default_printf_pointer_format): Define new function.
	* tree-pass.h (make_pass_sprintf_length): Declare new function.
	* print-tree.c: Increase buffer size.

gcc/c-family/ChangeLog:

	PR middle-end/49905
	* c.opt: Add -Wformat-length and -fprintf-return-value.

gcc/testsuite/ChangeLog:

	PR middle-end/49905
	* gcc.dg/builtin-stringop-chk-1.c: Adjust.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-2.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-3.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-warn-4.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf.c: New test.
	* gcc.dg/tree-ssa/builtin-sprintf-2.c: New test.

From-SVN: r240298

1 files changed, 17 insertions, 0 deletions

diff --git a/gcc/config/linux.c b/gcc/config/linux.c
index 16c3768..9aac38b 100644
--- a/gcc/config/linux.c
+++ b/gcc/config/linux.c
@@ -21,8 +21,12 @@ along with GCC; see the file COPYING3.  If not see
 #include "system.h"
 #include "coretypes.h"
 #include "tm.h"
+#include "tree.h"
 #include "linux-protos.h"
 
+#undef TARGET_PRINTF_POINTER_FORMAT
+#define TARGET_PRINTF_POINTER_FORMAT gnu_libc_printf_pointer_format
+
 bool
 linux_libc_has_function (enum function_class fn_class)
 {
@@ -36,3 +40,16 @@ linux_libc_has_function (enum function_class fn_class)
 
   return false;
 }
+
+/* Glibc formats pointers as if by "%zx" except for the null pointer
+   which outputs "(nil)".  It ignores the pound ('#') format flag but
+   interprets the space and plus flags the same as in the integer
+   directive.  */
+
+const char*
+gnu_libc_printf_pointer_format (tree arg, const char **flags)
+{
+  *flags = " +";
+
+  return arg && integer_zerop (arg) ? "(nil)" : "%#zx";
+}