Ingo reported following build failure:

On Sat, Feb 11, 2017 at 12:12:34PM +0100, Ingo Molnar wrote:
>
> So I had this oldish 32-bit 15.10 Ubuntu installation around (fully updated), and
> trying to build perf gave me:
>
> deimos:~/tip/tools/perf> make
>   BUILD:   Doing 'make -j4' parallel build
> make[3]: *** No rule to make target '/usr/include/x86_64-linux-gnu/sys/types.h', needed by 'fixdep.o'.  Stop.
> Makefile:42: recipe for target 'fixdep-in.o' failed
> make[2]: *** [fixdep-in.o] Error 2
> /home/mingo/tip/tools/build/Makefile.include:4: recipe for target 'fixdep' failed
> make[1]: *** [fixdep] Error 2
> Makefile:68: recipe for target 'all' failed
> make: *** [all] Error 2
>
> Now this got a bit better after I did a 'make mrproper' in the kernel tree:
>
> deimos:~/tip/tools/perf> make
>   BUILD:   Doing 'make -j4' parallel build
>   HOSTCC   fixdep.o
> /home/mingo/tip/tools/build/fixdep: 1: /home/mingo/tip/tools/build/fixdep: Syntax error: "(" unexpected...