re PR c++/55149 (capturing VLA in lambda)

	PR c++/55149
	* semantics.c (add_capture): Error rather than abort on copy
	capture of VLA.
	* typeck.c (maybe_warn_about_returning_address_of_local): Don't
	warn about capture proxy.

From-SVN: r198776

gcc/cp/ChangeLog

+2013-05-10  Jason Merrill  <jason@redhat.com>
+
+	PR c++/55149
+	* semantics.c (add_capture): Error rather than abort on copy
+	capture of VLA.
+	* typeck.c (maybe_warn_about_returning_address_of_local): Don't
+	warn about capture proxy.
+
 2013-05-09  Jason Merrill  <jason@redhat.com>
 
 	* decl.c (cp_finish_decl): Only check VLA bound in C++1y mode.

gcc/cp/semantics.c

@@ -9463,9 +9463,12 @@ add_capture (tree lambda, tree id, tree initializer, bool by_reference_p,
   type = lambda_capture_field_type (initializer, explicit_init_p);
   if (array_of_runtime_bound_p (type))
     {
+      if (!by_reference_p)
+	error ("array of runtime bound cannot be captured by copy, "
+	       "only by reference");
+
       /* For a VLA, we capture the address of the first element and the
 	 maximum index, and then reconstruct the VLA for the proxy.  */
-      gcc_assert (by_reference_p);
       tree elt = cp_build_array_ref (input_location, initializer,
 				     integer_zero_node, tf_warning_or_error);
       tree ctype = vla_capture_type (type);

gcc/cp/typeck.c

@@ -8140,6 +8140,7 @@ maybe_warn_about_returning_address_of_local (tree retval)
   if (DECL_P (whats_returned)
       && DECL_NAME (whats_returned)
       && DECL_FUNCTION_SCOPE_P (whats_returned)
+      && !is_capture_proxy (whats_returned)
       && !(TREE_STATIC (whats_returned)
 	   || TREE_PUBLIC (whats_returned)))
     {

gcc/testsuite/g++.dg/cpp1y/vla5.C

+// PR c++/55149
+// { dg-options -std=c++1y }
+
+void test(int n) {
+  int r[n];
+  [&r]() { return r + 0; };
+  [r]() { return r + 0; };	// { dg-error "captured by copy" }
+}