Create live_switch_vars conditionally (PR sanitizer/78270)

	PR sanitizer/78270
	* gcc.dg/asan/pr78270.c: New test.
	PR sanitizer/78270
	* gimplify.c (gimplify_switch_expr): Create live_switch_vars
	only when SWITCH_BODY is a BIND_EXPR.

From-SVN: r242036

gcc/ChangeLog

+2016-11-10  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/78270
+	* gimplify.c (gimplify_switch_expr): Create live_switch_vars
+	only when SWITCH_BODY is a BIND_EXPR.
+
 2016-11-10  Pierre-Marie de Rodat  <derodat@adacore.com>
 
 	PR debug/78112

gcc/gimplify.c

@@ -2241,7 +2241,7 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
     {
       vec<tree> labels;
       vec<tree> saved_labels;
-      hash_set<tree> *saved_live_switch_vars;
+      hash_set<tree> *saved_live_switch_vars = NULL;
       tree default_case = NULL_TREE;
       gswitch *switch_stmt;
 
@@ -2253,8 +2253,14 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
          labels.  Save all the things from the switch body to append after.  */
       saved_labels = gimplify_ctxp->case_labels;
       gimplify_ctxp->case_labels.create (8);
-      saved_live_switch_vars = gimplify_ctxp->live_switch_vars;
-      gimplify_ctxp->live_switch_vars = new hash_set<tree> (4);
+
+      /* Do not create live_switch_vars if SWITCH_BODY is not a BIND_EXPR.  */
+      if (TREE_CODE (SWITCH_BODY (switch_expr)) == BIND_EXPR)
+	{
+	  saved_live_switch_vars = gimplify_ctxp->live_switch_vars;
+	  gimplify_ctxp->live_switch_vars = new hash_set<tree> (4);
+	}
+
       bool old_in_switch_expr = gimplify_ctxp->in_switch_expr;
       gimplify_ctxp->in_switch_expr = true;
 
@@ -2269,8 +2275,12 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
 
       labels = gimplify_ctxp->case_labels;
       gimplify_ctxp->case_labels = saved_labels;
-      gcc_assert (gimplify_ctxp->live_switch_vars->elements () == 0);
-      delete gimplify_ctxp->live_switch_vars;
+
+      if (gimplify_ctxp->live_switch_vars)
+	{
+	  gcc_assert (gimplify_ctxp->live_switch_vars->elements () == 0);
+	  delete gimplify_ctxp->live_switch_vars;
+	}
       gimplify_ctxp->live_switch_vars = saved_live_switch_vars;
 
       preprocess_case_label_vec_for_gimple (labels, index_type,

gcc/testsuite/ChangeLog

+2016-11-10  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/78270
+	* gcc.dg/asan/pr78270.c: New test.
+
 2016-11-10  Pierre-Marie de Rodat  <derodat@adacore.com>
 	    Jakub Jelinek  <jakub@redhat.com>
 

gcc/testsuite/gcc.dg/asan/pr78270.c

+// { dg-do compile }
+// { dg-additional-options "-Wno-switch-unreachable" }
+
+typedef struct
+{
+} bdaddr_t;
+
+int a;
+void fn1 ()
+{
+  switch (a)
+    &(bdaddr_t){};
+}