Binary package “libiomp-dev” in ubuntu bionic

Intel OpenMP runtime - dev package - transition package

 The runtime is the part of the OpenMP implementation that your code is
 linked against, and that manages the multiple threads in an OpenMP program
 while it is executing.
 .
 This package has been replaced by the LLVM sources. This is the Intel version
 moved under the LLVM umbrella. This is a dependency package.