Re: [PR69315] enable finish_function to recurse for constexpr functions

[Jason Merrill <jason at redhat dot com>]

On 01/26/2016 12:11 PM, Alexandre Oliva wrote:
> We don't want finish_function to be called recursively from mark_used.
> However, it's desirable and necessary to call itself recursively when
> performing delayed folding, because that may have to instantiate and
> evaluate constexpr template functions.

Hmm.  If recursion is problematic, we shouldn't do it.  If it isn't 
problematic, we can do away with defer_mark_used_calls.  It doesn't make 
sense to me to allow recursion some of the time.

I tried disabling defer_mark_used_calls, and the only new testsuite 
failure turned out to be fixing a bug on variadic122.C: we were 
deferring a mark_used call in unevaluated context and then calling it in 
evaluated context.

Jakub, you added defer_mark_used_calls for BZ 37189, do you think it's 
still needed?  The testcase passes without it now.

Jason