pt.c (make_fnparm_pack): Split out from...

[thirdparty/gcc.git] / gcc / cp / pt.c

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 1c408237c6f3a7a08ede804cde19f65834f35d3a..5092c72b17749d69d741cf3e147b2d96dc8f688c 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -174,6 +174,7 @@ static tree tsubst (tree, tree, tsubst_flags_t, tree);
 static tree tsubst_expr        (tree, tree, tsubst_flags_t, tree, bool);
 static tree tsubst_copy        (tree, tree, tsubst_flags_t, tree);
 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
+static tree tsubst_decl (tree, tree, tsubst_flags_t);
 
 /* Make the current scope suitable for access checking when we are
    processing T.  T can be FUNCTION_DECL for instantiated function
@@ -7435,6 +7436,37 @@ tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
   return r;
 }
 
+/* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
+   NONTYPE_ARGUMENT_PACK.  */
+
+static tree
+make_fnparm_pack (tree spec_parm)
+{
+  /* Collect all of the extra "packed" parameters into an
+     argument pack.  */
+  tree parmvec;
+  tree parmtypevec;
+  tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
+  tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
+  int i, len = list_length (spec_parm);
+
+  /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters.  */
+  parmvec = make_tree_vec (len);
+  parmtypevec = make_tree_vec (len);
+  for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
+    {
+      TREE_VEC_ELT (parmvec, i) = spec_parm;
+      TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
+    }
+
+  /* Build the argument packs.  */
+  SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
+  SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
+  TREE_TYPE (argpack) = argtypepack;
+
+  return argpack;
+}        
+
 /* Substitute ARGS into T, which is an pack expansion
    (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
    TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
@@ -7449,6 +7481,7 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
   tree first_arg_pack; int i, len = -1;
   tree result;
   int incomplete = 0;
+  bool very_local_specializations = false;
 
   gcc_assert (PACK_EXPANSION_P (t));
   pattern = PACK_EXPANSION_PATTERN (t);
@@ -7465,7 +7498,18 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
       tree orig_arg = NULL_TREE;
 
       if (TREE_CODE (parm_pack) == PARM_DECL)
-       arg_pack = retrieve_local_specialization (parm_pack);
+       {
+         arg_pack = retrieve_local_specialization (parm_pack);
+         if (arg_pack == NULL_TREE)
+           {
+             /* This can happen for a parameter name used later in a function
+                declaration (such as in a late-specified return type).  Just
+                make a dummy decl, since it's only used for its type.  */
+             gcc_assert (skip_evaluation);
+             arg_pack = tsubst_decl (parm_pack, args, complain);
+             arg_pack = make_fnparm_pack (arg_pack);
+           }
+       }
       else
         {
           int level, idx, levels;
@@ -7559,6 +7603,17 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
   if (len < 0)
     return error_mark_node;
 
+  if (!local_specializations)
+    {
+      /* We're in a late-specified return type, so we don't have a local
+        specializations table.  Create one for doing this expansion.  */
+      very_local_specializations = true;
+      local_specializations = htab_create (37,
+                                          hash_local_specialization,
+                                          eq_local_specializations,
+                                          NULL);
+    }
+
   /* For each argument in each argument pack, substitute into the
      pattern.  */
   result = make_tree_vec (len + incomplete);
@@ -7620,7 +7675,7 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
          break;
        }
     }
-  
+
   /* Update ARGS to restore the substitution from parameter packs to
      their argument packs.  */
   for (pack = packs; pack; pack = TREE_CHAIN (pack))
@@ -7643,6 +7698,12 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
         }
     }
 
+  if (very_local_specializations)
+    {
+      htab_delete (local_specializations);
+      local_specializations = NULL;
+    }
+  
   return result;
 }
 
@@ -15477,37 +15538,12 @@ instantiate_decl (tree d, int defer_ok,
        }
       if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
         {
-          /* Collect all of the extra "packed" parameters into an
-             argument pack.  */
-          tree parmvec;
-          tree parmtypevec;
-          tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
-          tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
-          int i, len = 0;
-          tree t;
-          
-          /* Count how many parameters remain.  */
-          for (t = spec_parm; t; t = TREE_CHAIN (t))
-            len++;
-
-          /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters.  */
-          parmvec = make_tree_vec (len);
-          parmtypevec = make_tree_vec (len);
-          for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
-            {
-              TREE_VEC_ELT (parmvec, i) = spec_parm;
-              TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
-            }
-
-          /* Build the argument packs.  */
-          SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
-          SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
-          TREE_TYPE (argpack) = argtypepack;
-          
           /* Register the (value) argument pack as a specialization of
              TMPL_PARM, then move on.  */
+         tree argpack = make_fnparm_pack (spec_parm);
           register_local_specialization (argpack, tmpl_parm);
           tmpl_parm = TREE_CHAIN (tmpl_parm);
+         spec_parm = NULL_TREE;
         }
       gcc_assert (!spec_parm);