Re: [libcxx22] fallout

On Tue, Aug 25, 2026 at 09:55:53PM +0200, Rafael Sadowski wrote:
> On Fri Aug 21, 2026 at 02:15:34PM +0200, Theo Buehler wrote:
> > Here is the directly libcxx22-related breakage of my first bulk.
> > 
> > There may be a few more because mono got stuck with a weird error.  And
> > I did not try to build the V8 monsters: codex, deno, chromiums and a few
> > others because my machine isn't beefy enough. I don't think anything
> > super important is directly affected or hiding behind those. So as far
> > as ports are concerned, I think we can land libcxx22 whenever we want:
> > 
> > audio/ncmpcpp
> > audio/rubberband
> > cad/freecad
> > databases/mongodb/44
> > games/cataclysm-dda
> > games/dxx-rebirth
> > games/flightgear/base
> > games/keeperrl
> > mail/kopano/core
> > misc/subsurface
> > shells/fish/v3
> > textproc/lttoolbox
> > 
> > 
> > misc/subsurface
> > /usr/ports/pobj/subsurface-6.0.5459/subsurface-e0fbda77ef203a5a2539465e9fa44df56e2f5a9e/core/uemis-downloader.cpp:434:9: error: null passed to a callee that requires a non-null argument [-Werror,
> > -Wnonnull]
> >   434 |         return NULL;
> >       |                ^~~~
> 
> OK?
> 
> diff --git a/misc/subsurface/patches/patch-core_uemis-downloader_cpp b/misc/subsurface/patches/patch-core_uemis-downloader_cpp
> new file mode 100644
> index 00000000000..85c640885f3
> --- /dev/null
> +++ b/misc/subsurface/patches/patch-core_uemis-downloader_cpp
> @@ -0,0 +1,21 @@
> +Index: core/uemis-downloader.cpp
> +--- core/uemis-downloader.cpp.orig
> ++++ core/uemis-downloader.cpp
> +@@ -194,7 +194,7 @@ static struct dive *get_dive_by_uemis_diveid(device_da
> + 		if (object_id == d->dcs[0].diveid)
> + 			return d.get();
> + 	}
> +-	return NULL;
> ++	return {};

Maybe there is some C++ magic that fixes this, but I don't think this is
right. The return value is assigned to a non_owned_dive (since the
divelist is an owning_table containing unique_ptrs). Doesn't this leak?

> + }
> + 
> + /* send text to the importer progress bar */
> +@@ -431,7 +431,7 @@ static std::string first_object_id_val(std::string_vie
> + 			return res;
> + 		}
> + 	}
> +-	return NULL;
> ++	return {};

this seems fine.

> + }
> + 
> + /* ultra-simplistic; it doesn't deal with the case when the object_id is