Initialize live_switch_vars for SWITCH_BODY == STATEMENT_LIST (PR sanitizer/80879).

2017-06-19  Martin Liska  <mliska@suse.cz>

	PR sanitizer/80879
	* gimplify.c (gimplify_switch_expr):
	Initialize live_switch_vars for SWITCH_BODY == STATEMENT_LIST.
2017-06-19  Martin Liska  <mliska@suse.cz>

	PR sanitizer/80879
	* gcc.dg/asan/use-after-scope-switch-4.c: New test.

From-SVN: r249368

gcc/ChangeLog

 2017-06-19  Martin Liska  <mliska@suse.cz>
 
+	PR sanitizer/80879
+	* gimplify.c (gimplify_switch_expr):
+	Initialize live_switch_vars for SWITCH_BODY == STATEMENT_LIST.
+
+2017-06-19  Martin Liska  <mliska@suse.cz>
+
 	* doc/install.texi: Document that PGO runs in 4 stages.
 
 2017-06-19  Martin Liska  <mliska@suse.cz>

gcc/gimplify.c

@@ -2279,7 +2279,8 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
 
       /* Do not create live_switch_vars if SWITCH_BODY is not a BIND_EXPR.  */
       saved_live_switch_vars = gimplify_ctxp->live_switch_vars;
-      if (TREE_CODE (SWITCH_BODY (switch_expr)) == BIND_EXPR)
+      tree_code body_type = TREE_CODE (SWITCH_BODY (switch_expr));
+      if (body_type == BIND_EXPR || body_type == STATEMENT_LIST)
 	gimplify_ctxp->live_switch_vars = new hash_set<tree> (4);
       else
 	gimplify_ctxp->live_switch_vars = NULL;

gcc/testsuite/ChangeLog

 2017-06-19  Martin Liska  <mliska@suse.cz>
 
+	PR sanitizer/80879
+	* gcc.dg/asan/use-after-scope-switch-4.c: New test.
+
+2017-06-19  Martin Liska  <mliska@suse.cz>
+
 	PR ipa/80732
 	* gcc.target/i386/mvc5.c: Scan indirect_function.
 	* gcc.target/i386/mvc7.c: Likewise.

gcc/testsuite/gcc.dg/asan/use-after-scope-switch-4.c

+// { dg-do run }
+// { dg-additional-options "-fdump-tree-gimple" }
+
+int *ptr;
+
+struct a
+{
+  int c;
+};
+
+int main(int argc, char **argv)
+{
+  struct a e;
+  e.c = 2;
+  int x = 0;
+
+  for (;;)
+    switch (e.c)    
+      case 3:
+	{
+	  int resxxx;
+	case 2:
+	  ptr = &resxxx;
+	  *ptr = 123;
+
+	  if (x)
+	    return 0;
+	  else
+	    x = 1;
+	}
+
+  return 1;
+}
+
+/* { dg-final { scan-tree-dump-times "ASAN_MARK \\(UNPOISON, &resxxx, \[0-9\]\\);" 2 "gimple" } }  */