The following packages will be installed:
 steamos-xpad 
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make -C /lib/modules/4.4.276/build V=1 M=/usr/src/slapt-src-x86_64/system/steamos-xpad/steamos-xpad-f5f73eb modules
make[1]: *** /lib/modules/4.4.276/build: No such file or directory.  Stop.
make: *** [Makefile:5: all] Error 2
fakeroot -- sh steamos-xpad.SlackBuild Failed