Firstly, you have to make sure that you have correctly installed LLVM. If you haven't, you should visit this page and follow the instructions there.
After that, you'll need to set an environment variable LLVM_HOME which points to correctly installed LLVM directory (usually it's /usr/local/). And thirdly, you have to clone this repository anywhere you want and build the project:
git clone https://github.com/kibrq/ub-tester-tool.git
cd ub-tester-tool
mkdir build && cd build
cmake ..
makeBy executing these commands you'll get a file ub-tester.
To use our application, you have to add #include with path to file UBTester.h in include folder of our project (if you follow the Installation step, the path will be '../UBTester.h') to the file(-s) which you want to test. Then you can run ub_tester on these file(-s). It will generate IMPROVED_ versions of your files. Now you can compile these new files, but that requires the following flags:
-I. -I[path-to-UBTester.h] -DUB_TESTER -std=c++17.