Evaluate a SAVE_EXPR before an UBSAN check (PR sanitizer/80350).

2017-04-10  Martin Liska  <mliska@suse.cz>

	PR sanitizer/80350
	* c-ubsan.c (ubsan_instrument_shift): Evaluate RHS before
	doing an UBSAN check.
2017-04-10  Martin Liska  <mliska@suse.cz>

	PR sanitizer/80350
	* c-c++-common/ubsan/pr80350.c: New test.

From-SVN: r246799

gcc/c-family/ChangeLog

+2017-04-10  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/80350
+	* c-ubsan.c (ubsan_instrument_shift): Evaluate RHS before
+	doing an UBSAN check.
+
 2017-04-03  Jonathan Wakely  <jwakely@redhat.com>
 
 	* c-warn.c (do_warn_double_promotion): Fix typo in comment.

gcc/c-family/c-ubsan.c

@@ -172,6 +172,7 @@ ubsan_instrument_shift (location_t loc, enum tree_code code,
   /* In case we have a SAVE_EXPR in a conditional context, we need to
      make sure it gets evaluated before the condition.  */
   t = fold_build2 (COMPOUND_EXPR, TREE_TYPE (t), unshare_expr (op0), t);
+  t = fold_build2 (COMPOUND_EXPR, TREE_TYPE (t), unshare_expr (op1), t);
 
   enum sanitize_code recover_kind = SANITIZE_SHIFT_EXPONENT;
   tree else_t = void_node;

gcc/testsuite/ChangeLog

+2017-04-10  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/80350
+	* c-c++-common/ubsan/pr80350.c: New test.
+
 2017-04-10  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/80324

gcc/testsuite/c-c++-common/ubsan/pr80350.c

+/* PR target/80310 */
+/* { dg-do run } */
+/* { dg-options "-O0 -fsanitize=shift -fno-sanitize-recover=shift" } */
+
+unsigned int x = 1;
+unsigned int y = 0;
+
+void foo() {
+  y = 1 >> (!x * 1111);
+}
+
+int main () {
+    foo ();
+    if (y != 1)
+      __builtin_abort ();
+    return 0;
+}