How to set MKL on Linux with Cmake - c++

Question

I've used the same code provided in this link
How to setup MKL on linux with CMake
But i'm getting this error
Could NOT find MKL (missing: MKL_LIBRARIES MKL_INCLUDE_DIRS
I've tried to set MKLROOT to the following
SET(ENV{MKLROOT} "/home/usr/intel/mkl:$ENV{MKLROOT}")
This is how findmkl.cmake module looks like without the line of code to set the environment for mklroot (i've used the same code in the link below)
https://gist.github.com/scivision/5108cf6ab1515f581a84cd9ad1ef72aa
i suspect the issue is setting the mklroot but not sure, any help is appreciated.

Answer 1

If MKLROOT is initially unset, the statement SET(ENV{MKLROOT} "/home/usr/intel/mkl:$ENV{MKLROOT}") sets MKLROOT equal to /home/usr/intel/mkl:, which is an incorrect format for the path. Instead, you could use
set(ENV{MKLROOT} "/home/usr/intel/mkl")
Alternatively, you can set the value of that environment variable externally, e.g.,
source /home/usr/intel/bin/compilervars.sh intel64
and then run CMake. In that case, there is no need for the CMake set statement, which is a more portable solution.
UPDATE: As of 20th Feb 2021 compilervars.sh is not provided within Intel MKL and the environment should be set with the following command:
source /opt/intel/oneapi/setvars.sh intel64
or wherever oneAPI is installed.