Hello, starting from 15.0.7, I contributed several patches for building clang/llvm with Cygwin. At that time, clang was the only way for building executables for Windows On ARM64 without using MSVC, so I made some packages for CYGWIN with the newer versions. Nowaday, this is not true anymore because GCC15 allows to create an aarch64-w64-mingw32 cross compiler that can be used for this purpose, so I stopped to update it after version 18.
Me too I got the "export ordinal too large" error and unfortunately there is not much to do for bypassing it if you build a monolithic shared library. However, there is another way for bypassing this issue, by creating smaller shared libraries instead of a single gigantic DLL. You can do it by adding: -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=Release to CMake and it will work. IMPORTANT: If you have your locale set on a language different than english, don't forget to add this environment variable: export LANG=C otherwise GNU LD won't be detected by CMake, see here: https://github.com/llvm/llvm-project/issues/62634 I had contributed a patch for fixing it long time ago: https://github.com/llvm/llvm-project/pull/95913 but unfortunately it has not been committed yet, as far as I know. I hope that you will find it useful. Sincerely, Carlo Bramini. Il giorno dom 13 apr 2025 alle ore 21:34 Jeremy Drake via Cygwin-apps <cygwin-apps@cygwin.com> ha scritto: > > On Sat, 12 Apr 2025, Jeremy Drake via Cygwin-apps wrote: > > > Maybe setting -DCMAKE_CXX_STANDARD=20 would work around this? It would at > > least take a different path in that if/elif block in basic_string. > > It does indeed work around this, and builds a functional dylib llvm/clang > on Cygwin. > > > But I > > think we need to figure out why the extern template isn't working > > regardless. > > I opened https://github.com/msys2/MSYS2-packages/issues/5329 . If this > reproduces with a mingw-w64 libstdc++ built with the gcc4 abi option, > I would feel more comfortable opening an issue with llvm/llvm-project than > I would for a target that already requires a bunch of non-upstreamed hacks > to work at all.
