[Bug c++/68703] __attribute__((vector_size(N))) template member confusion

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68703

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Not really sure if this is about dependent type or not, because the following
fails too:
template <typename V>
struct D {
  V v;
  int f1 () { return this->v[N-1]; }
  int f2 () { return v[N-1]; }
};

int
main ()
{
  typedef int V1 __attribute__((vector_size (4 * sizeof (int))));
  typedef int V2 __attribute__((vector_size (8 * sizeof (int))));
  D<V1> a = { { 0, 1, 2, 3 } };
  D<V2> b = { { 0, 1, 2, 3, 4, 5, 6, 7 } };
  if (a.f1 () != 3 || a.f2 () != 3
      || b.f1 () != 7 || b.f2 () != 7)
    __builtin_abort ();
}

I've tried:
--- pt.c.jj4    2016-08-06 12:11:45.000000000 +0200
+++ pt.c (TREE_C2016-08-08 20:03:33.217898449 +0200
@@ -22687,6 +22687,11 @@ dependent_type_p_r (tree type)D (expression, 0));
      if       (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
     return true;_CODE (expression) == OFFSET_REF)
        {
+  /* Types with dependent vector_size attribute are dependent.  */, 0)))
+  tree a = lookup_attribute ("vector_size", TYPE_ATTRIBUTES (type));
+  if (a && ATTR_IS_DEPENDENT (a))D (expression, 1);
+    return true;ntifier_p (expression))
+           return false;
   /* Other types are non-dependent.  */
   return false;EF with non-null TREE_TYPE is always non-dependent.  */
 }
@@ -23166,6 +23171,18 @@ type_dependent_expression_p (tree expres
   if (TREE_CODE (expression) == EXPR_PACK_EXPANSION)
     return true;

+  /* Decls where the type is going to have dependent vector_size attribute
+     are dependent.  */
+  if (VAR_P (expression)
+      || TREE_CODE (expression) == PARM_DECL
+      || TREE_CODE (expression) == RESULT_DECL
+      || TREE_CODE (expression) == FIELD_DECL)
+    {
+      tree a = lookup_attribute ("vector_size", DECL_ATTRIBUTES (expression));
+      if (a && ATTR_IS_DEPENDENT (a))
+       return true;
+    }
+
   if (TREE_TYPE (expression) == unknown_type_node)
     {
       if (TREE_CODE (expression) == ADDR_EXPR)

so far but it didn't make any difference, neither on
template <int N>
struct D {
  int v __attribute__((vector_size (N * sizeof (int))));
  int f1 () { return this->v[N-1]; }
  int f2 () { return v[N-1]; }
};

int
main ()
{
  D<4> a = { { 0, 1, 2, 3 } };
  D<8> b = { { 0, 1, 2, 3, 4, 5, 6, 7 } };
  if (a.f1 () != 3 || a.f2 () != 3
      || b.f1 () != 7 || b.f2 () != 7)
    __builtin_abort ();
}

nor on
template <int N>
struct D {
  typedef int V __attribute__((vector_size (N * sizeof (int))));
  V v;
  int f1 () { return this->v[N-1]; }
  int f2 () { return v[N-1]; }
};

int
main ()
{
  D<4> a = { { 0, 1, 2, 3 } };
  D<8> b = { { 0, 1, 2, 3, 4, 5, 6, 7 } };
  if (a.f1 () != 3 || a.f2 () != 3
      || b.f1 () != 7 || b.f2 () != 7)
    __builtin_abort ();
}