DKMS make.log for broadcom-wl-6.20.155.1 for kernel 3.8.2-1-ARCH (x86_64)
Fri  8 Mar 16:40:04 GMT 2013
make: Entering directory `/usr/src/linux-3.8.2-1-ARCH'
CFG80211 API is prefered for this kernel version
Using CFG80211 API
Building for x86_64
  LD      /var/lib/dkms/broadcom-wl/6.20.155.1/build/built-in.o
  CC [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/src/shared/linux_osl.o
  CC [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_linux.o
  CC [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_iw.o
  CC [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_cfg80211.o
/var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_cfg80211.c:1613:2: warning: initialization from incompatible pointer type [enabled by default]
/var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_cfg80211.c:1613:2: warning: (near initialization for ‘wl_cfg80211_ops.set_tx_power’) [enabled by default]
/var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_cfg80211.c:1614:2: warning: initialization from incompatible pointer type [enabled by default]
/var/lib/dkms/broadcom-wl/6.20.155.1/build/src/wl/sys/wl_cfg80211.c:1614:2: warning: (near initialization for ‘wl_cfg80211_ops.get_tx_power’) [enabled by default]
  LD [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/wl.o
  Building modules, stage 2.
CFG80211 API is prefered for this kernel version
Using CFG80211 API
Building for x86_64
  MODPOST 1 modules
WARNING: "rcu_read_unlock_special" [/var/lib/dkms/broadcom-wl/6.20.155.1/build/wl.ko] undefined!
WARNING: modpost: Found 1 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
  CC      /var/lib/dkms/broadcom-wl/6.20.155.1/build/wl.mod.o
  LD [M]  /var/lib/dkms/broadcom-wl/6.20.155.1/build/wl.ko
make: Leaving directory `/usr/src/linux-3.8.2-1-ARCH'