[C++ PATCH] Refactor implicit function template implementation and fix 58534, 58536, 58548, 58549 and 58637.

[Jason Merrill]

On 11/11/2013 02:44 PM, Adam Butcher wrote:
>> Yes, using add_outermost_template_args.
>>
> I have done this (diff -w -b follows).  The route to this seems even
> more costly though; current_template_parms needs to first be converted
> to a vec by current_template_args() then the last nesting level is
> thrown away and replaced with the one we're working on.

True.  It looks like you could avoid the wasted conversion of the 
innermost level by doing

template_parms_to_args (TREE_CHAIN (current_template_parms))

rather than

current_template_args.

The patch is OK with or without that change.

Jason