Makefile race in 4.9-rc3 (generated/autoksyms.h: No such file or directory)

[Ken Moffat]

I just tried to build 4.9 (rc3) for the first time (x86_64, i7 haswell)
 After making my choices in make oldconfig, make -j8 failed in
less than 2 sec.

   CC      scripts/mod/empty.o
  HOSTCC  scripts/mod/mk_elfconfig
  HOSTCC  scripts/sortextable
  CC      scripts/mod/devicetable-offsets.s
In file included from ./include/linux/linkage.h:6:0,
                 from ./include/linux/kernel.h:6,
                 from ./include/asm-generic/bug.h:13,
                 from ./arch/x86/include/asm/bug.h:35,
                 from ./include/linux/bug.h:4,
                 from ./include/linux/jump_label.h:170,
                 from ./arch/x86/include/asm/string_64.h:5,
                 from ./arch/x86/include/asm/string.h:4,
                 from ./include/linux/string.h:18,
                 from ./include/uapi/linux/uuid.h:21,
                 from ./include/linux/uuid.h:19,
                 from ./include/linux/mod_devicetable.h:12,
                 from scripts/mod/devicetable-offsets.c:2:
./include/linux/export.h:81:33: fatal error: generated/autoksyms.h: No
such file or directory
 #include <generated/autoksyms.h>
                                 ^
compilation terminated.
make[2]: *** [scripts/Makefile.build:154:
scripts/mod/devicetable-offsets.s] Error 1
make[1]: *** [scripts/Makefile.build:475: scripts/mod] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:559: scripts] Error 2
make: *** Waiting for unfinished jobs....

I then ran make clean and gave it another try, again using -j8.
This time i t worked, so I guess there is a race in a Makefile.

Äen