[C++ PATCH] method vec

[Nathan Sidwell <nathan at acm dot org>]

This preparatory patch fixes up a couple of places where a non-function 
could start appearing in the METHOD_VEC.  The warn_hidden change looks 
bigger than necessary, because of indentation change.  I noticed 
check_classfn could check a template mismatch earlier, and avoid doing 
some work.

applied to trunk.

nathan
--
Nathan Sidwell

2017-09-06  Nathan Sidwell  <nathan@acm.org>

	* class.c (warn_hidden): Don't barf on non-functions.
	* decl2.c (check_classfn): Likewise.  Check template match earlier.

Index: class.c
===================================================================
--- class.c	(revision 251782)
+++ class.c	(working copy)
@@ -2818,63 +2818,64 @@ check_for_override (tree decl, tree ctyp
 static void
 warn_hidden (tree t)
 {
-  vec<tree, va_gc> *method_vec = CLASSTYPE_METHOD_VEC (t);
-  tree fns;
-
-  /* We go through each separately named virtual function.  */
-  for (int i = 0; vec_safe_iterate (method_vec, i, &fns); ++i)
-    {
-      tree name = OVL_NAME (fns);
-      auto_vec<tree, 20> base_fndecls;
-      tree base_binfo;
-      tree binfo;
-      int j;
+  if (vec<tree, va_gc> *method_vec = CLASSTYPE_METHOD_VEC (t))
+    for (unsigned ix = method_vec->length (); ix--;)
+      {
+	tree fns = (*method_vec)[ix];
 
-      /* Iterate through all of the base classes looking for possibly
-	 hidden functions.  */
-      for (binfo = TYPE_BINFO (t), j = 0;
-	   BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
-	{
-	  tree basetype = BINFO_TYPE (base_binfo);
-	  get_basefndecls (name, basetype, &base_fndecls);
-	}
+	if (!OVL_P (fns))
+	  continue;
 
-      /* If there are no functions to hide, continue.  */
-      if (base_fndecls.is_empty ())
-	continue;
+	tree name = OVL_NAME (fns);
+	auto_vec<tree, 20> base_fndecls;
+	tree base_binfo;
+	tree binfo;
+	unsigned j;
+
+	/* Iterate through all of the base classes looking for possibly
+	   hidden functions.  */
+	for (binfo = TYPE_BINFO (t), j = 0;
+	     BINFO_BASE_ITERATE (binfo, j, base_binfo); j++)
+	  {
+	    tree basetype = BINFO_TYPE (base_binfo);
+	    get_basefndecls (name, basetype, &base_fndecls);
+	  }
 
-      /* Remove any overridden functions.  */
-      for (ovl_iterator iter (fns); iter; ++iter)
-	{
-	  tree fndecl = *iter;
-	  if (TREE_CODE (fndecl) == FUNCTION_DECL
-	      && DECL_VINDEX (fndecl))
-	    {
-	      /* If the method from the base class has the same
-		 signature as the method from the derived class, it
-		 has been overridden.  */
-	      for (size_t k = 0; k < base_fndecls.length (); k++)
-		if (base_fndecls[k]
-		    && same_signature_p (fndecl, base_fndecls[k]))
-		  base_fndecls[k] = NULL_TREE;
-	    }
-	}
+	/* If there are no functions to hide, continue.  */
+	if (base_fndecls.is_empty ())
+	  continue;
 
-      /* Now give a warning for all base functions without overriders,
-	 as they are hidden.  */
-      size_t k;
-      tree base_fndecl;
-      FOR_EACH_VEC_ELT (base_fndecls, k, base_fndecl)
-	if (base_fndecl)
+	/* Remove any overridden functions.  */
+	for (ovl_iterator iter (fns); iter; ++iter)
 	  {
-	    /* Here we know it is a hider, and no overrider exists.  */
-	    warning_at (location_of (base_fndecl),
-			OPT_Woverloaded_virtual,
-			"%qD was hidden", base_fndecl);
-	    warning_at (location_of (fns),
-			OPT_Woverloaded_virtual, "  by %qD", fns);
+	    tree fndecl = *iter;
+	    if (TREE_CODE (fndecl) == FUNCTION_DECL
+		&& DECL_VINDEX (fndecl))
+	      {
+		/* If the method from the base class has the same
+		   signature as the method from the derived class, it
+		   has been overridden.  */
+		for (size_t k = 0; k < base_fndecls.length (); k++)
+		  if (base_fndecls[k]
+		      && same_signature_p (fndecl, base_fndecls[k]))
+		    base_fndecls[k] = NULL_TREE;
+	      }
 	  }
-    }
+
+	/* Now give a warning for all base functions without overriders,
+	   as they are hidden.  */
+	tree base_fndecl;
+	FOR_EACH_VEC_ELT (base_fndecls, j, base_fndecl)
+	  if (base_fndecl)
+	    {
+	      /* Here we know it is a hider, and no overrider exists.  */
+	      warning_at (location_of (base_fndecl),
+			  OPT_Woverloaded_virtual,
+			  "%qD was hidden", base_fndecl);
+	      warning_at (location_of (fns),
+			  OPT_Woverloaded_virtual, "  by %qD", fns);
+	    }
+      }
 }
 
 /* Recursive helper for finish_struct_anon.  */
@@ -6981,7 +6982,7 @@ unreverse_member_declarations (tree t)
 
   /* For the TYPE_FIELDS, only the non TYPE_DECLs are in reverse
      order, so we can't just use nreverse.  Due to stat_hack
-     chicanery in finish_member_declarations.  */
+     chicanery in finish_member_declaration.  */
   prev = NULL_TREE;
   for (x = TYPE_FIELDS (t);
        x && TREE_CODE (x) != TYPE_DECL;
Index: decl2.c
===================================================================
--- decl2.c	(revision 251782)
+++ decl2.c	(working copy)
@@ -611,6 +611,15 @@ check_classfn (tree ctype, tree function
   for (ovl_iterator iter (fns); !matched && iter; ++iter)
     {
       tree fndecl = *iter;
+
+      /* A member template definition only matches a member template
+	 declaration.  */
+      if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL))
+	continue;
+
+      if (!DECL_DECLARES_FUNCTION_P (fndecl))
+	continue;
+
       tree p1 = TYPE_ARG_TYPES (TREE_TYPE (function));
       tree p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
 
@@ -625,11 +634,6 @@ check_classfn (tree ctype, tree function
 	  && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE)
 	p1 = TREE_CHAIN (p1);
 
-      /* A member template definition only matches a member template
-	 declaration.  */
-      if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL))
-	continue;
-
       /* ref-qualifier or absence of same must match.  */
       if (type_memfn_rqual (TREE_TYPE (function))
 	  != type_memfn_rqual (TREE_TYPE (fndecl)))