[svn r118] Fixed dynamic casts.

Fixed a few interface bugs.

test/classes9.d

@@ -0,0 +1,47 @@
+module classes9;
+
+class C
+{
+}
+
+class D : C
+{
+}
+
+class E
+{
+}
+
+class F : E
+{
+}
+
+void main()
+{
+    {
+        D d = new D;
+        {
+            C c = d;
+            assert(c !is null);
+            D d2 = cast(D)c;
+            assert(d2 !is null);
+            E e = cast(E)d;
+            assert(e is null);
+            F f = cast(F)d;
+            assert(f is null);
+        }
+    }
+    {
+        F f = new F;
+        {
+            E e = f;
+            assert(e !is null);
+            F f2 = cast(F)e;
+            assert(f2 !is null);
+            C c = cast(C)f;
+            assert(c is null);
+            D d2 = cast(D)f;
+            assert(d2 is null);
+        }
+    }
+}

test/interface5.d

@@ -0,0 +1,32 @@
+module interface5;
+
+interface I
+{
+    void func();
+}
+
+class C : I
+{
+    int i;
+    void func()
+    {
+        printf("C\n");
+        i++;
+    }
+}
+
+void main()
+{
+    C c = new C;
+    c.func();
+    {
+        I i = c;
+        c.func();
+
+        C c2 = cast(C)i;
+        c2.func();
+
+        c.func();
+        assert(c.i == 4);
+    }
+}

test/interface6.d

@@ -0,0 +1,44 @@
+module interface6;
+
+interface I
+{
+    void Ifunc();
+}
+
+interface J
+{
+    void Jfunc();
+}
+
+class C : I,J
+{
+    int i;
+    int j;
+    void Ifunc()
+    {
+        i++;
+    }
+    void Jfunc()
+    {
+        j++;
+    }
+}
+
+void main()
+{
+    C c = new C;
+    c.Ifunc();
+    c.Jfunc();
+    I i = c;
+    i.Ifunc();
+    J j = c;
+    j.Jfunc();
+    C c2 = cast(C)i;
+    c2.Ifunc();
+    c2.Jfunc();
+    C c3 = cast(C)j;
+    c3.Ifunc();
+    c3.Jfunc();
+    assert(c.i == 4);
+    assert(c.j == 4);
+}

test/interface7.d

@@ -0,0 +1,21 @@
+module interface7;
+
+interface I
+{
+}
+
+class C : I
+{
+}
+
+void main()
+{
+    I i = new C;
+    ClassInfo ci = i.classinfo;
+    char[] name = ci.name;
+    printf("ci.name = %.*s\n", name.length, name.ptr);
+    ClassInfo cI = I.classinfo;
+    name = cI.name;
+    printf("cI.name = %.*s\n", name.length, name.ptr);
+    assert(ci is cI);
+}