cc: error: unknown argument: '-fformat-extensions' when building kernel

[kareem33]

Hello.
I want to build custom kernel (which should include drivers for my WiFi USB adapter).
When I try to run:

make buildkernel KERNCONF=MYKERNEL

it stops with error:

cc: error: unknown argument: '-fformat-extensions'

Could anybody help me?
My custom kernel config and session output in attachement.

It is FreeBSD 12.1 on amd64.

 

[SirDice]

which should include drivers for my WiFi USB adapter

Most common Wifi drivers are already included in GENERIC. There's rarely a need to build a custom kernel. And those that aren't built-in can easily be dynamically loaded.

 

[kareem33]

Hello.
These are rtwn and rtwn_usb. I'm new to FreeBSD (but experienced user of other unix-like systems) - but according to my findings, these aren't included by default.

 

[Mjölnir]

You can load most kernel modules at boot with e.g. sysrc kld_list+=" rtwn" (this adds it to rc.conf(5), note the space), or add if_rtwn_usb_load="YES" to loader.conf(5). The general guideline is to only load vital kernel modules in loader.conf(5), i.e. those that are needed to access the root filesystem or provide other features needed to boot, and load all other kernel modules via kld_list in rc.conf[.local]. To load at runtime (i.e. now), use kldload rtwn_usb. Very few modules can only be loaded via xyz_load="YES" in loader.conf(5), these are obviously exceptions to that rule.

 

[kareem33]

Thanks.
Now modules seem to be loaded correctly, but still I cannot connect... I've created new post in proper section regarding this...