networkmanager fails to compile with -fno-common, which will be default in gcc-10.
Should be good in 1.18.6 per upstream NEWS at least. Masked version may still be broken, but it's masked and I'll try to make sure to remember to make sure this is there (picked from upstream branch if needed) before anything is unmasked.
Would appreciate a confirmation that it's fine in 1.18.6.
Created attachment 640236 [details]
Confirmed that 1.18.6 compiled successfully with gcc10
net-misc/networkmanager-1.22.10-r11::gentoo compiled fine with gcc-10.