OS X build fails due to missing elf.h

[FiloSottile]

make[2]: Entering directory '/Users/filippo/build/musl-cross-make/linux-4.4.10'
make[3]: Entering directory '/Users/filippo/build/musl-cross-make/build-x86_64-linux-musl/obj_kernel_headers'
  CHK     include/generated/uapi/linux/version.h
  UPD     include/generated/uapi/linux/version.h
  HOSTCC  scripts/basic/fixdep
  WRAP    arch/x86/include/generated/asm/clkdev.h
  WRAP    arch/x86/include/generated/asm/cputime.h
  WRAP    arch/x86/include/generated/asm/dma-contiguous.h
  WRAP    arch/x86/include/generated/asm/early_ioremap.h
  WRAP    arch/x86/include/generated/asm/mcs_spinlock.h
  WRAP    arch/x86/include/generated/asm/mm-arch-hooks.h
  SYSTBL  arch/x86/entry/syscalls/../../include/generated/asm/syscalls_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_32.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_64.h
  SYSHDR  arch/x86/entry/syscalls/../../include/generated/uapi/asm/unistd_x32.h
  HOSTCC  arch/x86/tools/relocs_32.o
In file included from /Users/filippo/build/musl-cross-make/linux-4.4.10/arch/x86/tools/relocs_32.c:1:
/Users/filippo/build/musl-cross-make/linux-4.4.10/arch/x86/tools/relocs.h:12:10: fatal error: 'elf.h' file not found
#include <elf.h>
         ^
1 error generated.
scripts/Makefile.host:108: recipe for target 'arch/x86/tools/relocs_32.o' failed
make[4]: *** [arch/x86/tools/relocs_32.o] Error 1
arch/x86/Makefile:193: recipe for target 'archscripts' failed
make[3]: *** [archscripts] Error 2
make[3]: Leaving directory '/Users/filippo/build/musl-cross-make/build-x86_64-linux-musl/obj_kernel_headers'
Makefile:146: recipe for target 'sub-make' failed
make[2]: *** [sub-make] Error 2
make[2]: Leaving directory '/Users/filippo/build/musl-cross-make/linux-4.4.10'
Makefile:196: recipe for target 'obj_kernel_headers/.lc_built' failed
make[1]: *** [obj_kernel_headers/.lc_built] Error 2
make[1]: Leaving directory '/Users/filippo/build/musl-cross-make/build-x86_64-linux-musl'
Makefile:152: recipe for target 'all' failed
make: *** [all] Error 2

TARGET = x86_64-linux-musl
OUTPUT = /usr/local/Cellar/musl-cross-make/HEAD

[richfelker]

I can't see why the tool that's failing is even being built for a headers_install target. This is probably a kernel bug (gratuitous dependencies in the makefile). Can you try one of the other supported kernel-header versions (see hashes dir for a list)? Or if you can find the cause of the wrong dependency we could perhaps add a patch to suppress it. Note that the breakage only happens on platforms without <elf.h>.

[FiloSottile]

Found it. I'll make a patch. diorcety/crosstool-ng#11

BTW, ec0f9f1 mentions 3.x kernels, but in hashes I only see 2.6.

Also, building against 2.6 works.

[richfelker]

Do you know if this issue is still present in upstream kernel? I've added support for 4.19 headers and will be dropping the old 4.4 headers that this patch was applied to, because 4.4 headers are not compatible with time64.