Description:
Attempting to compile aufs2 (2.6.36_20101021) against kernel26 (2.6.36.1-3) fails with compiler errors (details below).
It looks like aufs2-2.6.36.patch should have been applied to the kernel source tree (it's in the GIT repository) but hasn't made it into the kernel patch tarball (patch-2.6.36.1-3-ARCH.bz2).

Workaround:
Manually pulling aufs2-2.6.36.patch from GIT and applying it to the kernel source tree allowed me to compile aufs2.

Additional info:
aufs2 - 2.6.36_20101021
kernel26 - 2.6.36.1-3

Steps to reproduce:
- Copy aufs2 from /var/abs/extra to build directory
- makepkg

Error messages:

CC [M] .../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.o
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c: In function ‘au_br_mod_files_ro’:
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:861:9: error: implicit declaration of function ‘files_lglock_global_lock’
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:862:2: error: implicit declaration of function ‘do_file_list_for_each_entry’
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:862:40: error: expected ‘;’ before ‘{’ token
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:907:2: error: implicit declaration of function ‘files_lglock_global_unlock’
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:923:1: warning: label ‘out_free’ defined but not used
.../aufs2/src/aufs2-2.6.36_20101021/fs/aufs/branch.c:847:16: warning: unused variable ‘bstart’