Ubuntu 21.10 fails to compile OpenWrt 21.02 hosts tools (m4)

[Michal Vasilek]

On 10/18/21 4:54 PM, Hannu Nyman wrote:
> I noticed that Rosen has recently updated m4 in master to 1.4.19, so I 
> tested cherry-picking the 1.4.19 version update to openwrt-21.02, and it 
> helps. m4 again compiles  ;-)
>
> Apparently the m4 version 1.4.19 in master contains some fixes for host 
> gcc 11, or something similar?

This is probably because Ubuntu 21.10 has a new version of glibc which 
is not supported by 1.4.18, but is supported by 1.4.19.
https://lists.gnu.org/archive/html/bug-m4/2021-03/msg00000.html

There are pull requests on GitHub to backport the m4 updates to stable 
branches:
https://github.com/openwrt/openwrt/pull/4675

https://github.com/openwrt/openwrt/pull/4674