[C++ PATCH] Fix __direct_bases ICE (PR c++/85146)

[Jakub Jelinek]

Hi!

>From N2965 it is unclear to me what should the trait do on classes with
incomplete types, but given that __bases already returns an empty pack,
this patch does the same for __direct_bases.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2018-04-03  Jakub Jelinek  <ja...@redhat.com>

        PR c++/85146
        * semantics.c (calculate_direct_bases): Return empty vector if
        TYPE_BINFO is NULL.  Formatting fixes.

        * g++.dg/ext/bases3.C: New test.

--- gcc/cp/semantics.c.jj       2018-03-30 20:38:03.370202169 +0200
+++ gcc/cp/semantics.c  2018-04-03 09:32:38.462091604 +0200
@@ -3898,36 +3898,26 @@ calculate_direct_bases (tree type)
 
   complete_type (type);
 
-  if (!NON_UNION_CLASS_TYPE_P (type))
+  if (!NON_UNION_CLASS_TYPE_P (type) || !TYPE_BINFO (type))
     return make_tree_vec (0);
 
   base_binfos = BINFO_BASE_BINFOS (TYPE_BINFO (type));
 
   /* Virtual bases are initialized first */
   for (i = 0; base_binfos->iterate (i, &binfo); i++)
-    {
-      if (BINFO_VIRTUAL_P (binfo))
-       {
-         vec_safe_push (vector, binfo);
-       }
-    }
+    if (BINFO_VIRTUAL_P (binfo))
+      vec_safe_push (vector, binfo);
 
   /* Now non-virtuals */
   for (i = 0; base_binfos->iterate (i, &binfo); i++)
-    {
-      if (!BINFO_VIRTUAL_P (binfo))
-       {
-         vec_safe_push (vector, binfo);
-       }
-    }
-
+    if (!BINFO_VIRTUAL_P (binfo))
+      vec_safe_push (vector, binfo);
 
   bases_vec = make_tree_vec (vector->length ());
 
   for (i = 0; i < vector->length (); ++i)
-    {
-      TREE_VEC_ELT (bases_vec, i) = BINFO_TYPE ((*vector)[i]);
-    }
+    TREE_VEC_ELT (bases_vec, i) = BINFO_TYPE ((*vector)[i]);
+
   return bases_vec;
 }
 
--- gcc/testsuite/g++.dg/ext/bases3.C.jj        2018-04-03 09:39:49.547038799 
+0200
+++ gcc/testsuite/g++.dg/ext/bases3.C   2018-04-03 09:39:28.301041301 +0200
@@ -0,0 +1,13 @@
+// PR c++/85146
+// { dg-do compile { target c++11 } }
+
+template<typename...> struct A {};
+
+template<typename T> struct B
+{
+  typedef A<__direct_bases(T)...> C;
+};
+
+struct X;
+
+B<X> b;

        Jakub