> -- Could NOT find Git (missing: GIT_EXECUTABLE) 
> -- Could NOT find Git (missing: GIT_EXECUTABLE) (found version "")
> CMake Error at /usr/local/share/cmake/Modules/ExternalProject.cmake:2910 (message):
>   error: could not find git for clone of robinmap-populate
> Call Stack (most recent call first):
>   /usr/local/share/cmake/Modules/ExternalProject.cmake:4418 (_ep_add_download_command)
>   CMakeLists.txt:29 (ExternalProject_Add)

Sounds like it needs a bdep on git.

I had applied this patch (which fixes other defects in this CMakeFile):
https://marc.info/?l=openbsd-ports&m=170920085418634&w=2

and now my dpb got stuck in loops 

Detected loop, merging sets ok
| gnustep-base-1.29.0p1+gnustep-libobjc2-2.2p1+sope-5.9.1->gnustep-base-1.29.0p1+libdispatch-5.5p0+sope-5.9.1
Detected loop, merging sets ok
| gnustep-base-1.29.0p1+gnustep-libobjc2-2.2p1+sope-5.9.1->gnustep-base-1.29.0p1+libdispatch-5.5p0+sope-5.9.1
Detected loop, merging sets ok
| gnustep-base-1.29.0p1+gnustep-libobjc2-2.2p1+sope-5.9.1->gnustep-base-1.29.0p1+libdispatch-5.5p0+sope-5.9.1
Detected loop, merging sets ok
| gnustep-base-1.29.0p1+gnustep-libobjc2-2.2p1+sope-5.9.1->gnustep-base-1.29.0p1+libdispatch-5.5p0+sope-5.9.1
Detected loop, merging sets ok
| gnustep-base-1.29.0p1+gnustep-libobjc2-2.2