[C++ PATCH] Fix rejects-valid with value dependent array size (PR c++/33553)

[Jakub Jelinek]

Hi!

PR28595 added a check that when not at function scope
array bounds should must be integral constants expressions
(at function scope, when not in a local class, g++ allows VLAs
when not pedantic).  But if max is still value dependent during
tsubst, this rejected valid code as shown on the attached testcase.

Regtested on x86_64-linux, ok for trunk?

2008-02-04  Jakub Jelinek  <jakub@redhat.com>

	PR c++/33553
	* pt.c (tsubst) <case INTEGER_TYPE>: Don't issue error if max is
	value dependent expression.

	* g++.dg/template/array19.C: New test.

--- gcc/cp/pt.c.jj	2008-02-04 15:46:52.000000000 +0100
+++ gcc/cp/pt.c	2008-02-04 15:47:10.000000000 +0100
@@ -8894,9 +8894,9 @@ tsubst (tree t, tree args, tsubst_flags_
 			   /*integral_constant_expression_p=*/false);
 	max = fold_decl_constant_value (max);
 
-	if (TREE_CODE (max) != INTEGER_CST 
-	    && TREE_CODE (max) != TEMPLATE_PARM_INDEX
-	    && !at_function_scope_p ())
+	if (TREE_CODE (max) != INTEGER_CST
+	    && !at_function_scope_p ()
+	    && !value_dependent_expression_p (max))
 	  {
 	    if (complain & tf_error)
 	      error ("array bound is not an integer constant");
--- gcc/testsuite/g++.dg/template/array19.C.jj	2008-02-04 15:46:22.000000000 +0100
+++ gcc/testsuite/g++.dg/template/array19.C	2008-02-04 15:41:22.000000000 +0100
@@ -0,0 +1,22 @@
+// PR c++/33553
+// { dg-do compile }
+
+template <class T> struct S { static const int sz = 2; };
+template <class T> struct U { enum { sz = 2 }; };
+
+template <class R>
+struct P
+{
+  template <class T> void bar (int (&x)[S<T>::sz]);
+  template <class T> void baz (int (&x)[U<T>::sz]);
+};
+
+P<int> p;
+
+void
+foo (void)
+{
+  int x[2];
+  p.bar<int> (x);
+  p.baz<int> (x);
+}

	Jakub