https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114505
--- Comment #14 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #4)
> For the opposite direction, this is the fix:
> ```
> diff --git a/gcc/lto-compress.cc b/gcc/lto-compress.cc
> index c167ac967aa..1475674e7ac 100644
> --- a/gcc/lto-compress.cc
> +++ b/gcc/lto-compress.cc
> @@ -408,7 +408,7 @@ lto_end_uncompression (struct lto_compression_stream
> *stream,
> }
> #endif
> if (compression == ZSTD)
> - internal_error ("compiler does not support ZSTD LTO compression");
> + fatal_error ("compiler does not support ZSTD LTO compression");
>
> lto_uncompression_zlib (stream);
> }
> ```
>
> But this direction should work.
This looks obvious to push, btw. And yes, this was supposed to be "supported"
