I am getting this error on my laptop when I compile a kernel 4.16.x, or 4.17 or 4.14.48. I started with the LEAP 15.0 kernel config and ran make oldconfig, essentially going with the default answer (yes "" | make oldconfig). I have all of kernel-devel (except 32bit).
make: *** No rule to make target 'm', needed by 'certs/x509_certificate_list'. Stop.
make: *** [Makefile:1063: certs] Error 2
I don't get a bzImage. (4.16.x seems to keep compiling and even goes through modules and modules_install, but no bzImage.) I tried everything I know to remove what seems to be the offending part of the config, CONFIG_SYSTEM_DATA_VERIFICATION and all things related to X509, but that seems to be prevented by makefiles. I went searching for everything related to X509 in packman and the normal LEAP 15.0 repos, everything related seems to be installed.
Followed instructions aside from git. gcc and make are already installed. I also researched what packages exist in Slackware-14.3/d (development) and installed all of those (via zypper). Still getting the same error. I made sure I ran make mrproper beforehand. Still no dice.