Re: [PATCH][14 backport] c++: Fix instantiation of imported temploid friends [PR114275]

[Nathaniel Shead <nathanieloshead@gmail.com>]

On Thu, May 23, 2024 at 06:41:06PM -0400, Jason Merrill wrote:
> On 5/13/24 07:56, Nathaniel Shead wrote:
> > > > @@ -11751,9 +11767,16 @@ tsubst_friend_class (tree friend_tmpl, tree args)
> > > >          if (tmpl != error_mark_node)
> > > >    	{
> > > >    	  /* The new TMPL is not an instantiation of anything, so we
> > > > -	     forget its origins.  We don't reset CLASSTYPE_TI_TEMPLATE
> > > > +	     forget its origins.  It is also not a specialization of
> > > > +	     anything.  We don't reset CLASSTYPE_TI_TEMPLATE
> > > >    	     for the new type because that is supposed to be the
> > > >    	     corresponding template decl, i.e., TMPL.  */
> > > > +	  spec_entry elt;
> > > > +	  elt.tmpl = friend_tmpl;
> > > > +	  elt.args = CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl));
> > > > +	  elt.spec = TREE_TYPE (tmpl);
> > > > +	  type_specializations->remove_elt (&elt);
> > > 
> > > For GCC 14.2 let's guard this with if (modules_p ()); for GCC 15 it can be
> > > unconditional.  OK.
> > 
> > I'm looking to backport this patch to GCC 14 now that it's been on trunk
> > some time.  Here's the patch I'm aiming to add (squashed with the
> > changes from r15-220-gec2365e07537e8) after cherrypicking the
> > prerequisite commit r15-58-g2faf040335f9b4; is this OK?
> > 
> > Or should I keep it as two separate commits to make the cherrypicking
> > more obvious? Not entirely sure on the etiquette around this.
> 
> It's OK to squash them, but it's typical to use -x (directly or via git
> gcc-backport) to mention where a branch change was cherry-picked from, and
> in this case it would make sense to edit in the second commit so it's clear
> the backport includes both.  OK that way.
> 
> Jason
> 

Sorry, still a bit confused :)  Do you mean to merge the two commits
together such that there are two "cherry picked from commit ..."s in the
commit message?  Or just list second commit, and mention that it
includes both in the commit message?

Nathaniel