[Bug other/124446] --with-libiconv-prefix lacks multilib support

[bruno at clisp dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124446

--- Comment #2 from Bruno Haible <bruno at clisp dot org> ---
Indeed:

* config/iconv.m4 (serial 26), compared to the current version (serial 32) in
gnulib, lacks support for recent versions of macOS.

* config/lib-ld.m4 (serial 2), compared to the current version (serial 13) in
gnulib, lacks corrections for AIX and NetBSD.

* config/lib-link.m4 (serial 4), compared to the current version (serial 35) in
gnulib, lacks support for biarch platforms, for GNU/Hurd, for GNU/kFreeBSD, for
mingw, and corrections for OpenBSD and Solaris 10.

* config/lib-prefix.m4 (serial 2), compared to the current version (serial 23)
in gnulib, lacks support for biarch platforms and corrections for NetBSD,
Solaris OpenIndiana, and Solaris OmniOS.

* config/host-cpu-c-abi.m4 is a new dependency and will need to be added (from
gnulib) when the other files are upgraded.