[C++, concepts] Two slightly obscure pt.c functions?

[Paolo Carlini]

Hi,

in 2013 (2013-09-16) Adam added two slightly obscure functions and I 
can't find much around in terms of rationale, etc:

/* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto',
   'decltype(auto)' or a concept.  */

bool
is_auto_or_concept (const_tree type)
{
  return is_auto (type); // or concept
}

/* Returns the TEMPLATE_TYPE_PARM in TYPE representing a generic type 
(`auto' or
   a concept identifier) iff TYPE contains a use of a generic type.  
Returns
   NULL_TREE otherwise.  */

tree
type_uses_auto_or_concept (tree type)
{
  return find_type_usage (type, is_auto_or_concept);
}

The latter seems completely unused (it's meant for debugging purposes?); 
the former evidently simply forwards to is_auto, and we end up in the 
front-end with uses of both, which in fact are equivalent, which seems 
weird: IMHO, if they are actually equivalent in our implementation we 
should clearly explain that in the comment and have only one. Or what?

Thanks for any feedback,

Paolo.