nikic added a comment. In D125683#3815348 <https://reviews.llvm.org/D125683#3815348>, @ldionne wrote:
> In D125683#3811492 <https://reviews.llvm.org/D125683#3811492>, @nikic wrote: > >> I have some concerns about this change: >> >> - It makes it fundamentally impossible to link against a static >> system-libcxxabi (or any other `LIBCXX_CXX_ABI` option). This is currently >> already broken (https://github.com/llvm/llvm-project/issues/57759), but used >> to work prior to LLVM 15. >> - It makes it fundamentally impossible to use a linker script for the shared >> library while linking the abi library into the static library. I think this >> currently doesn't work either, but would be trivial to support. (I was going >> to work on this when I found this revision.) >> >> I think both of these points highlight that >> `LIBCXX_CXX_ABI=libcxxabi-objects` is not the correct representation for >> this functionality. > > I don't think these limitations are an inherent property of this approach. > What I'm trying to do with this change is eliminate these boolean flags that > control how we build the library to instead use a more open-ended selection > mechanism that is more flexible, more expressive, and which reduces the need > for `if(....)` within the build. > > I think the fundamental problem we have is that the ABI library for the > static libc++ and for the shared libc++ are selected in one go. If we could > instead specify the choice of the ABI library for each independently (for > example `-DLIBCXX_CXX_SHARED_ABI=libcxxabi > -DLIBCXX_CXX_STATIC_ABI=system-libcxxabi`), would that solve your problem? > Also, this would actually increase the flexibility of the current build by a > significant margin without much complexity on the libc++ CMake side. This would indeed address the second point, but not the first. For that, one would have to add additional variations like `system-libcxxabi-objects`, which would end up increasing the possible abi choices by a factor of two (unless static linking doesn't make sense for some of them). Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D125683/new/ https://reviews.llvm.org/D125683 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
