re PR c++/48446 (internal compiler error: in gimplify_var_or_parm_decl, at gimplify.c:1946)

	PR c++/48446
	* decl.c (compute_array_index_type): Use get_temp_regvar instead
	of variable_size.
	* init.c (get_temp_regvar): No longer static.
	* cp-tree.h: Declare it.

From-SVN: r172432

gcc/cp/ChangeLog

+2011-04-14  Jason Merrill  <jason@redhat.com>
+
+	PR c++/48446
+	* decl.c (compute_array_index_type): Use get_temp_regvar instead
+	of variable_size.
+	* init.c (get_temp_regvar): No longer static.
+	* cp-tree.h: Declare it.
+
 2011-04-14  Nicola Pero  <nicola.pero@meta-innovation.com>
 
 	* parser.c (cp_parser_objc_class_declaration): Updated for change

gcc/cp/cp-tree.h

@@ -4964,6 +4964,7 @@ extern tree build_offset_ref			(tree, tree, bool);
 extern tree build_new				(VEC(tree,gc) **, tree, tree,
 						 VEC(tree,gc) **, int,
                                                  tsubst_flags_t);
+extern tree get_temp_regvar			(tree, tree);
 extern tree build_vec_init			(tree, tree, tree, bool, int,
                                                  tsubst_flags_t);
 extern tree build_delete			(tree, tree,

gcc/cp/decl.c

@@ -7710,8 +7710,16 @@ compute_array_index_type (tree name, tree size, tsubst_flags_t complain)
       processing_template_decl = saved_processing_template_decl;
 
       if (!TREE_CONSTANT (itype))
-	/* A variable sized array.  */
-	itype = variable_size (itype);
+	{
+	  /* A variable sized array.  */
+	  if (TREE_SIDE_EFFECTS (itype))
+	    /* Use get_temp_regvar rather than variable_size here so that
+	       people walking expressions that use a variable of this type
+	       don't walk into this expression.  */
+	    itype = get_temp_regvar (TREE_TYPE (itype), itype);
+	  else
+	    itype = variable_size (itype);
+	}
       /* Make sure that there was no overflow when creating to a signed
 	 index type.  (For example, on a 32-bit machine, an array with
 	 size 2^32 - 1 is too big.)  */

gcc/cp/init.c

@@ -45,7 +45,6 @@ static void expand_virtual_init (tree, tree);
 static tree sort_mem_initializers (tree, tree);
 static tree initializing_context (tree);
 static void expand_cleanup_for_base (tree, tree);
-static tree get_temp_regvar (tree, tree);
 static tree dfs_initialize_vtbl_ptrs (tree, void *);
 static tree build_dtor_call (tree, special_function_kind, int);
 static tree build_field_list (tree, tree, int *);
@@ -2875,7 +2874,7 @@ create_temporary_var (tree type)
    things when it comes time to do final cleanups (which take place
    "outside" the binding contour of the function).  */
 
-static tree
+tree
 get_temp_regvar (tree type, tree init)
 {
   tree decl;

gcc/testsuite/ChangeLog

+2011-04-14  Jason Merrill  <jason@redhat.com>
+
+	* g++.dg/ext/vla10.C: New.
+
 2011-04-14  Richard Guenther  <rguenther@suse.de>
 
 	* gcc.dg/tree-ssa/ssa-dse-14.c: New testcase.

gcc/testsuite/g++.dg/ext/vla10.C

+// PR c++/48446
+// { dg-options "" }
+
+template<typename T>
+struct A
+{
+  ~A ();
+  T *operator-> () const;
+};
+
+struct B
+{
+  typedef A <B> P;
+  static P foo (int);
+};
+
+struct C
+{
+  typedef A<C> P;
+  static const int c = 80;
+};
+
+C::P bar ();
+
+void
+baz ()
+{
+  char z[bar ()->c];
+  {
+    B::P m = B::foo (sizeof (z));
+  }
+}