The example demonstrates how to use a module summary index file produced for ThinLTO to:
- find the module that defines the main entry point
- find all extra modules that are required for the build
A LIT test runs the example as part of the LLVM test suite  and shows how to create a module summary index file.
The code also provides two Error types that can be useful when working with ThinLTO summaries.
 if LLVM_BUILD_EXAMPLES=ON and platform is not Windows