Compiler option dependency for LLVM pass with CMake

Question

I have a project that needs to be built with an LLVM pass. Here is the project structure:

proj/
   instrumentation/
       CMakeLists.txt
       Instrumentation.cpp
   [My project files]
   CMakeLists.txt

instrumentation/CMakeLists.txt has a target to build the LLVM pass called MyPass.

I've added the following the CMakeLists.txt:

add_subdirectory(instrumentation)
add_compile_options(
            "SHELL:-Xclang -load"
            "SHELL:-Xclang $<TARGET_FILE:MyPass>")

Now I just need to add MyPass as a dependency for all the targets in my project. I was wondering if there was a way to force MyPass to build first so that when compiling other files, the LLVM pass would be present. Maybe there a way to add a target compile_options dependencies?

Note: I'd rather not add the dependency manually to every target because there many targets in the project.

Answer 1

My solution to this is to create another project to wrap the compiler executable and automatically build with the LLVM pass. Then rebuild the original project with the wrapped compiler.

AFL does this exact thing when building with a clang compiler.