symbol lookup error: /usr/sbin/ModemManager: undefined symbol: mm_location_3gpp_set_mobile_country_code after build

[Aleksander Morgado]

Hey,

>
> It seems that after that, ModemManager breaks, because the NetworkManager install is doing something to break it.
>

NetworkManager brings as dependency libmm-glib, and will install it in
the same location as your custom built libmm-glib.
The way to avoid this is to first install NM with the system-installed
libmm-glib, and then you install your custom built libmm-glib on top.
The libmm-glib is API/ABI compatible, so there is no risk of breaking
NM by using a custom built library.

-- 
Aleksander