undefined reference to `copy_siginfo_from_user32'

[Giuseppe Sacco <giuseppe@eppesuigoccas.homedns.org>]

Hi list,
since a few days, whenever I try to recompile the latest kernel (from git) it 
always print this error message:

[...]
  AS      arch/mips/lib/strlen_user.o
  AS      arch/mips/lib/strncpy_user.o
  AS      arch/mips/lib/strnlen_user.o
  CC      arch/mips/lib/uncached.o
  AR      arch/mips/lib/lib.a
  LD      vmlinux.o
  MODPOST vmlinux.o
WARNING: modpost: Found 11 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
  GEN     .version
  CHK     include/linux/compile.h
  UPD     include/linux/compile.h
  CC      init/version.o
  LD      init/built-in.o
  LD      .tmp_vmlinux1
kernel/built-in.o: In function `$L261':
ptrace.c:(.text+0x13550): undefined reference to `copy_siginfo_from_user32'
ptrace.c:(.text+0x13550): relocation truncated to fit: R_MIPS_26 against 
`copy_siginfo_from_user32'
make[1]: *** [.tmp_vmlinux1] Error 1
make[1]: Leaving directory `/usr/local/src/kernel/2.6.25'
make: *** [debian/stamp-build-kernel] Error 2

Any idea about a possible cause/solution?

Thank you very mcuh,
Giuseppe