building on ubuntu 20 is failing

[dbpaul]

Description

following the build instructions cmake .. CMake Error at /usr/lib/x86_64-linux-gnu/cmake/gflags/gflags-nonamespace-targets.cmake:37 (message): .......

Current Behavior

cmake fails

Possible Solution

add "apt purge libgflags*" to build instructions, then it is working. I guess you could also change something in the build script, but i have no clue about any of this.