it does build for linux-libre-lts

i think it's a package build issue: https://bugs.archlinux.org/task/63644

somewhat related: https://unix.stackexchange.com/questions/547159/how-to-rebuild-gcc-plugins-for-kernel-module

the only difference between the headers package i see between mainline and lts are that mainline contains the failing build/scripts/gcc-plugins/structleak_plugin.so but lts doesn't. i tried removing the file and any binary file in the gcc-plugins directory but now it complains it can't find the file

i fixed it like this, so i think it's a build issue (is the issue tracker indexed by search engines? it should be useful for people asking the same for arch and manjaro)

• download, unpack and patch linux-libre 5.3.7 sources from pkgbuild

```
wget https://linux-libre.fsfla.org/pub/linux-libre/releases/5.3-gnu/linux-libre-5.3-gnu.tar.xz \
https://linux-libre.fsfla.org/pub/linux-libre/releases/5.3.7-gnu/patch-5.3-gnu-5.3.7-gnu.xz
bsdtar xf linux-libre-5.3-gnu.tar.xz
unxz patch-5.3-gnu-5.3.7-gnu.xz
cd linux-5.3
patch -Np 1 -i ../patch-5.3-gnu-5.3.7-gnu
```

• Copy config

```
zcat /proc/config.gz > .config
```

• Build scripts, this builds gcc-plugins, and strip the broken plugin

```
make scripts
strip --strip-unneeded scripts/gcc-plugins/structleak_plugin.so
```

• Replace it and reinstall wireguard-dkms to rebuild modules

```
sudo cp -a scripts/gcc-plugins/structleak_plugin.so /lib/modules/5.3.7-gnu-1/build/scripts/gcc-plugins/
sudo pacman -S --noconfirm wireguard-dkms
```

I am facing this exact same issue both with wireguard-dkms and tp_smapi-dkms (probably affects all dkms builds).
Didn't had the time yet to try fauno's fix, though it seems it should be incorporated into the linux-libre build for the time being, while that structleak_plugin is broken.

Could you try with the latest linux-libre 5.3.8? Also, what GCC version are you using?

It builds successfully with linux-libre 5.3.8. Unfortunately I cannot test if the modules actually work because I am having another issue with 5.3.8: #2543
Anyway, upon a successful build these modules always worked, so I guess you can close this issue.

gcc 9.2.0-4 (base-devel)

This same exact issue has now re-emerged with linux-libre 5.5.x

Could you please apply the same fix as before?

DKMS make.log for wireguard-0.0.20200215 for kernel 5.5.1-gnu-1 (x86_64)
Sat 29 Feb 2020 17:46:32 WET
make: Entering directory '/usr/lib/modules/5.5.1-gnu-1/build'
  AR      /var/lib/dkms/wireguard/0.0.20200215/build/built-in.a
  CC [M]  /var/lib/dkms/wireguard/0.0.20200215/build/noise.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20200215/build/main.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20200215/build/device.o
  CC [M]  /var/lib/dkms/wireguard/0.0.20200215/build/peer.o
cc1: error: incompatible gcc/plugin versions
cc1: error: incompatible gcc/plugin versions
cc1: error: fail to initialize plugin ./scripts/gcc-plugins/structleak_plugin.so
cc1: error: fail to initialize plugin ./scripts/gcc-plugins/structleak_plugin.so
make[1]: *** [scripts/Makefile.build:266: /var/lib/dkms/wireguard/0.0.20200215/build/main.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make[1]: *** [scripts/Makefile.build:266: /var/lib/dkms/wireguard/0.0.20200215/build/noise.o] Error 1
cc1: error: incompatible gcc/plugin versions
cc1: error: fail to initialize plugin ./scripts/gcc-plugins/structleak_plugin.so
make[1]: *** [scripts/Makefile.build:266: /var/lib/dkms/wireguard/0.0.20200215/build/device.o] Error 1
cc1: error: incompatible gcc/plugin versions
cc1: error: fail to initialize plugin ./scripts/gcc-plugins/structleak_plugin.so
make[1]: *** [scripts/Makefile.build:266: /var/lib/dkms/wireguard/0.0.20200215/build/peer.o] Error 1
make: *** [Makefile:1693: /var/lib/dkms/wireguard/0.0.20200215/build] Error 2
make: Leaving directory '/usr/lib/modules/5.5.1-gnu-1/build'

confirmed it's happening again

Seems to be fixed on linux-libre 5.5.7