Hi Al,

FYI, kernel build failed on

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal.git master
head:   811a6550c2567601b6ea4799a44732f7dbab4807
commit: f3104017df8d227095cba60e27b836e49ee227c7 [54/62] avr32: sigaltstack conversion
config: avr32-atngw100_defconfig (attached as .config)

All related error/warning messages:

arch/avr32/kernel/signal.c: In function 'sys_rt_sigreturn':
arch/avr32/kernel/signal.c:88: error: implicit declaration of function 'sys_sigaltstack'

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0-DAY kernel build testing backend         Open Source Technology Centre
Fengguang Wu <wfg@linux.intel.com>                     Intel Corporation