Header Search Path Issues and C++ Interop

Using Swift
,
1

Hi. I have some c++ code that uses some embedded (copied over) files from another open source project (Asio). I have previously managed to make it compile as a standalone CMake library using c++ only (c++20).

Now I am trying to use SPM (Swift 6.0) to build a mixed language project, but it can never find my asio.hpp when I run swift build. Here is a link to the repository: GitHub - RussBaz/lumengine

Can anyone please advise how to properly set up my Package.swift file for this case? I am pretty sure it is related to the headerSearchPath, but I can never find the correct path.

Thank you!

2

I have progressed a bit further. By adding a public header path and a .cpp file and runing swift build, I am now getting different errors. Such as:

/Users/user/Projects/GitHub/lumengine/Sources/cxxLumengine/asio/include/asio/detail/io_uring_null_buffers_op.hpp:32:41: error: expected class name
 30 |
 31 | template <typename Handler, typename IoExecutor>
 32 | class io_uring_null_buffers_op : public io_uring_operation
    |                                         `- error: expected class name
 33 | {
 34 | public:

These errors are not part of my code, though.

However, this is not the strangest part because I managed to compile the project myself using clang++ and swiftc directly! Here are the two commands that I used successfully (from the project root):

clang++ -I./Sources/cxxLumengine/asio/include -I./Sources/cxxLumengine/include -D ASIO_STANDALONE -std=c++20 -c ./Sources/cxxLumengine/cxxLumengine.cpp -o output.o

swiftc -I ./Sources/cxxLumengine/include -Xcc -I./Sources/cxxLumengine/asio/include -D ASIO_STANDALONE -Xcc -std=c++20 -cxx-interoperability-mode=default -o lumengine.dylib -emit-library ./Sources/lumengine/lumengine.swift ./output.o