openmp wasn't detected on mac with installed llvm and libomp

[yqy6611]

Describe the bug

I have installed llvm and libomp successfully and set configure arguments, yet openmp still couldn't be detected.

Code for Reproduction

install.packages('abess', type = 'source')

Desktop (please complete the following information):

• OS: macOS sonoma
• R Version: 4.4.1
• Package Version: 0.4.9

Screenshots

• installing source package ‘abess’ ... ** package ‘abess’ successfully unpacked and MD5 sums checked ** using staged installation checking whether the C++ compiler works... yes checking for C++ compiler default output file name... a.out checking for suffix of executables... checking whether we are cross compiling... no checking for suffix of object files... o checking whether the compiler supports GNU C++... yes checking whether /opt/homebrew/opt/llvm/bin/clang++ accepts -g... yes checking for /opt/homebrew/opt/llvm/bin/clang++ option to enable C++11 features... none needed checking how to run the C++ preprocessor... /opt/homebrew/opt/llvm/bin/clang++ -E checking for gcc... /opt/homebrew/opt/llvm/bin/clang checking whether the compiler supports GNU C... yes checking whether /opt/homebrew/opt/llvm/bin/clang accepts -g... yes checking for /opt/homebrew/opt/llvm/bin/clang option to enable C11 features... none needed checking how to run the C preprocessor... /opt/homebrew/opt/llvm/bin/clang -E Spectra library exists. Complier code exists in src/ directory. Install R package according to the complier code. checking whether OpenMP will work in a package... no OpenMP is unavailable on this Mac OSX system. Training speed may be suboptimal. To use all CPU cores for training jobs, you should install OpenMP by running

         brew install libomp
  

configure: creating ./config.status config.status: creating src/Makevars