call.c (build_new_method_call): Handle getting a TEMPLATE_ID_EXPR around a TEMPLATE_DECL.

	* call.c (build_new_method_call): Handle getting a
 	TEMPLATE_ID_EXPR around a TEMPLATE_DECL.  Don't look for a field
 	if we got template parms.
	* typeck.c (build_x_function_call): Remember the TEMPLATE_ID_EXPR,
 	not just the args.
	* decl2.c (build_expr_from_tree): Tweak last change.
	* pt.c (tsubst_copy): Use get_first_fn instead of TREE_VALUE.
	(maybe_fold_nontype_arg): Split out from tsubst_copy.
	* tree.c (get_first_fn): Just return a TEMPLATE_ID_EXPR.

Mon Nov 10 20:08:38 1997  Kriang Lerdsuwanakij <lerdsuwa@scf-fs.usc.edu>

	* pt.c (tsubst_copy): Handle explicit template arguments in
	function calls.
	* typeck.c (build_x_function_call): Likewise.
	* decl2.c (build_expr_from_tree): Lookup function name if it
	hasn't been done.

	* pt.c (tsubst): Instantiate template functions properly when
	template parameter does not appear in function arguments and return
	type.
	(comp_template_args): Handle member templates required by tsubst.

From-SVN: r16427

6 files changed, 117 insertions, 44 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index bd15ca1..b267d28 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -4,6 +4,31 @@ Sun Nov  9 01:29:55 1997  Jim Wilson  (wilson@cygnus.com)
 	* init.c (build_vec_delete_1): Delete build_block and
 	add_block_current_level calls.
 
+Mon Nov 10 20:25:31 1997  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* call.c (build_new_method_call): Handle getting a
+ 	TEMPLATE_ID_EXPR around a TEMPLATE_DECL.  Don't look for a field
+ 	if we got template parms.
+	* typeck.c (build_x_function_call): Remember the TEMPLATE_ID_EXPR,
+ 	not just the args.
+	* decl2.c (build_expr_from_tree): Tweak last change.
+	* pt.c (tsubst_copy): Use get_first_fn instead of TREE_VALUE.
+	(maybe_fold_nontype_arg): Split out from tsubst_copy.
+	* tree.c (get_first_fn): Just return a TEMPLATE_ID_EXPR.
+
+Mon Nov 10 20:08:38 1997  Kriang Lerdsuwanakij <lerdsuwa@scf-fs.usc.edu>
+
+	* pt.c (tsubst_copy): Handle explicit template arguments in 
+	function calls.
+	* typeck.c (build_x_function_call): Likewise.
+	* decl2.c (build_expr_from_tree): Lookup function name if it 
+	hasn't been done.
+
+	* pt.c (tsubst): Instantiate template functions properly when 
+	template parameter does not appear in function arguments and return 
+	type.
+	(comp_template_args): Handle member templates required by tsubst.
+
 Mon Nov 10 20:08:38 1997  Jason Merrill  <jason@yorick.cygnus.com>
 
 	* decl.c (grokdeclarator): Tweak conditions for pedwarn in
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index eaa39c6..da1d50c 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -5474,6 +5474,8 @@ build_new_method_call (instance, name, args, basetype_path, flags)
     {
       explicit_targs = TREE_OPERAND (name, 1);
       name = TREE_OPERAND (name, 0);
+      if (TREE_CODE (name) == TEMPLATE_DECL)
+	name = DECL_NAME (name);
       template_only = 1;
     }
 
@@ -5526,10 +5528,13 @@ build_new_method_call (instance, name, args, basetype_path, flags)
     {
       instance_ptr = build_this (instance);
 
-      /* XXX this should be handled before we get here.  */
-      fns = build_field_call (basetype_path, instance_ptr, name, args);
-      if (fns)
-	return fns;
+      if (! template_only)
+	{
+	  /* XXX this should be handled before we get here.  */
+	  fns = build_field_call (basetype_path, instance_ptr, name, args);
+	  if (fns)
+	    return fns;
+	}
     }
   else
     {
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index b51e660..5d94797 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -3406,10 +3406,9 @@ build_expr_from_tree (t)
 	return do_identifier (TREE_OPERAND (t, 0), 0);
 
     case TEMPLATE_ID_EXPR:
-      return lookup_template_function (build_expr_from_tree
-				       (TREE_OPERAND (t, 0)),
-				       build_expr_from_tree
-				       (TREE_OPERAND (t, 1)));
+      return (lookup_template_function
+	      (build_expr_from_tree (TREE_OPERAND (t, 0)),
+	       build_expr_from_tree (TREE_OPERAND (t, 1))));
 
     case INDIRECT_REF:
       return build_x_indirect_ref
@@ -3568,7 +3567,8 @@ build_expr_from_tree (t)
       else
 	{
 	  tree name = TREE_OPERAND (t, 0);
-	  if (! really_overloaded_fn (name))
+	  if (TREE_CODE (name) == TEMPLATE_ID_EXPR
+	      || ! really_overloaded_fn (name))
 	    name = build_expr_from_tree (name);
 	  return build_x_function_call
 	    (name, build_expr_from_tree (TREE_OPERAND (t, 1)),
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index dff871d..8e05af3 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -1157,7 +1157,13 @@ comp_template_args (oldargs, newargs)
 	continue;
       if (TREE_CODE (nt) != TREE_CODE (ot))
 	return 0;
-      if (TREE_CODE_CLASS (TREE_CODE (ot)) == 't')
+      if (TREE_CODE (nt) == TREE_VEC)
+        {
+          /* For member templates */
+	  if (comp_template_args (nt, ot))
+	    continue;
+        }
+      else if (TREE_CODE_CLASS (TREE_CODE (ot)) == 't')
 	{
 	  if (comptypes (ot, nt, 1))
 	    continue;
@@ -2025,6 +2031,39 @@ lookup_nested_type_by_name (ctype, name)
   return NULL_TREE;
 }
 
+/* If arg is a non-type template parameter that does not depend on template
+   arguments, fold it like we weren't in the body of a template.  */
+
+static tree
+maybe_fold_nontype_arg (arg)
+     tree arg;
+{
+  if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't'
+      && !uses_template_parms (arg))
+    {
+      /* Sometimes, one of the args was an expression involving a
+	 template constant parameter, like N - 1.  Now that we've
+	 tsubst'd, we might have something like 2 - 1.  This will
+	 confuse lookup_template_class, so we do constant folding
+	 here.  We have to unset processing_template_decl, to
+	 fool build_expr_from_tree() into building an actual
+	 tree.  */
+
+      int saved_processing_template_decl = processing_template_decl; 
+      processing_template_decl = 0;
+      arg = fold (build_expr_from_tree (arg));
+      processing_template_decl = saved_processing_template_decl; 
+    }
+  return arg;
+}
+
+/* Take the tree structure T and replace template parameters used therein
+   with the argument vector ARGS.  NARGS is the number of args; should
+   be removed.  IN_DECL is an associated decl for diagnostics.
+
+   tsubst is used for dealing with types, decls and the like; for
+   expressions, use tsubst_expr or tsubst_copy.  */
+
 tree
 tsubst (t, args, nargs, in_decl)
      tree t, args;
@@ -2246,14 +2285,6 @@ tsubst (t, args, nargs, in_decl)
 	    type = tsubst (type, args, nargs, in_decl);
 	  }
 
-	if (type == TREE_TYPE (t)
-	    && (! member || ctx == DECL_CLASS_CONTEXT (t)))
-	  {
-	    t = copy_node (t);
-	    copy_lang_decl (t);
-	    return t;
-	  }
-
 	/* Do we already have this instantiation?  */
 	if (DECL_TEMPLATE_INFO (t) != NULL_TREE)
 	  {
@@ -2262,7 +2293,8 @@ tsubst (t, args, nargs, in_decl)
 
 	    for (; decls; decls = TREE_CHAIN (decls))
 	      if (TREE_TYPE (TREE_VALUE (decls)) == type
-		  && DECL_CLASS_CONTEXT (TREE_VALUE (decls)) == ctx)
+		  && DECL_CLASS_CONTEXT (TREE_VALUE (decls)) == ctx
+		  && comp_template_args (TREE_PURPOSE (decls), args))
 		return TREE_VALUE (decls);
 	  }
 
@@ -2616,24 +2648,8 @@ tsubst (t, args, nargs, in_decl)
 
 	for (i = 0; i < len; i++)
 	  {
-	    elts[i] = tsubst_expr (TREE_VEC_ELT (t, i), args, nargs, in_decl);
-
-	    if (TREE_CODE_CLASS (TREE_CODE (elts[i])) != 't'
-		&& !uses_template_parms (elts[i]))
-	      {
-		/* Sometimes, one of the args was an expression involving a
-		   template constant parameter, like N - 1.  Now that we've
-		   tsubst'd, we might have something like 2 - 1.  This will
-		   confuse lookup_template_class, so we do constant folding
-		   here.  We have to unset processing_template_decl, to
-		   fool build_expr_from_tree() into building an actual
-		   tree.  */
-
-		int saved_processing_template_decl = processing_template_decl; 
-		processing_template_decl = 0;
-		elts[i] = fold (build_expr_from_tree (elts[i]));
-		processing_template_decl = saved_processing_template_decl; 
-	      }
+	    elts[i] = maybe_fold_nontype_arg
+	      (tsubst_expr (TREE_VEC_ELT (t, i), args, nargs, in_decl));
 
 	    if (elts[i] != TREE_VEC_ELT (t, i))
 	      need_new = 1;
@@ -2847,6 +2863,10 @@ do_poplevel ()
   return t;
 }
 
+/* Like tsubst, but deals with expressions.  This function just replaces
+   template parms; to finish processing the resultant expression, use
+   tsubst_expr.  */
+
 tree
 tsubst_copy (t, args, nargs, in_decl)
      tree t, args;
@@ -2966,7 +2986,7 @@ tsubst_copy (t, args, nargs, in_decl)
       {
 	tree fn = TREE_OPERAND (t, 0);
 	if (really_overloaded_fn (fn))
-	  fn = tsubst_copy (TREE_VALUE (fn), args, nargs, in_decl);
+	  fn = tsubst_copy (get_first_fn (fn), args, nargs, in_decl);
 	else
 	  fn = tsubst_copy (fn, args, nargs, in_decl);
 	return build_nt
@@ -3028,10 +3048,14 @@ tsubst_copy (t, args, nargs, in_decl)
 
     case TEMPLATE_ID_EXPR:
       {
-	tree r = lookup_template_function
-	  (tsubst_copy (TREE_OPERAND (t, 0), args, nargs, in_decl),
-	   tsubst_copy (TREE_OPERAND (t, 1), args, nargs, in_decl));
-	return r;
+        /* Substituted template arguments */
+	tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, nargs, in_decl);
+	tree chain;
+	for (chain = targs; chain; chain = TREE_CHAIN (chain))
+	  TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain));
+
+	return lookup_template_function
+	  (tsubst_copy (TREE_OPERAND (t, 0), args, nargs, in_decl), targs);
       }
 
     case TREE_LIST:
@@ -3089,6 +3113,8 @@ tsubst_copy (t, args, nargs, in_decl)
     }
 }
 
+/* Like tsubst_copy, but also does semantic processing and RTL expansion.  */
+
 tree
 tsubst_expr (t, args, nargs, in_decl)
      tree t, args;
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index 9d2589f..e94fd55 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -1306,7 +1306,8 @@ tree
 get_first_fn (from)
      tree from;
 {
-  if (TREE_CODE (from) == FUNCTION_DECL 
+  if (TREE_CODE (from) == FUNCTION_DECL
+      || TREE_CODE (from) == TEMPLATE_ID_EXPR
       || DECL_FUNCTION_TEMPLATE_P (from))
     return from;
 
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 4b774d2..54f8c83 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -2281,6 +2281,7 @@ build_x_function_call (function, params, decl)
      tree function, params, decl;
 {
   tree type;
+  tree template_id = NULL_TREE;
   int is_method;
 
   if (function == error_mark_node)
@@ -2289,6 +2290,13 @@ build_x_function_call (function, params, decl)
   if (processing_template_decl)
     return build_min_nt (CALL_EXPR, function, params, NULL_TREE);
 
+  /* Save explicit template arguments if found */
+  if (TREE_CODE (function) == TEMPLATE_ID_EXPR)
+    {
+      template_id = function;
+      function = TREE_OPERAND (function, 0);
+    }
+
   type = TREE_TYPE (function);
 
   if (TREE_CODE (type) == OFFSET_TYPE
@@ -2383,6 +2391,9 @@ build_x_function_call (function, params, decl)
 	  decl = build_indirect_ref (decl, NULL_PTR);
 	}
 
+      /* Put back explicit template arguments, if any.  */
+      if (template_id)
+        function = template_id;
       return build_method_call (decl, function, params,
 				NULL_TREE, LOOKUP_NORMAL);
     }
@@ -2411,7 +2422,12 @@ build_x_function_call (function, params, decl)
 	  tree val = TREE_VALUE (function);
 
 	  if (flag_ansi_overloading)
-	    return build_new_function_call (function, params, NULL_TREE);
+	    {
+	      /* Put back explicit template arguments, if any.  */
+	      if (template_id)
+		function = template_id;
+	      return build_new_function_call (function, params, NULL_TREE);
+	    }
 
 	  if (TREE_CODE (val) == TEMPLATE_DECL)
 	    return build_overload_call_real