On Fri, Jul 28, 2017 at 10:20:33AM +0200, Marc Espie wrote: > On Fri, Jul 28, 2017 at 06:50:35AM +0200, Sebastien Marie wrote: > > Hi, > > > > I would like to understand the rationale about the addition of > > COMPILER_LIBCXX in WANTLIB on lang/rust. > > > > lang/rust is compiled using ports gcc4.9. The c++ library used is > > libestdc++. And the use of devel/llvm is due linkage with LLVM libraries > > (base isn't suitable for that: we don't have libLLVM*.so but only > > clang/clang++). > > > > Previously, the WANTLIB for main was: > > > > rust-1.18.0$ make show=WANTLIB-main > > estdc++>=17 c m pthread z > > > > > > Now, the WANTLIB-main has c++ and c++abi added, and estdc++ is missing: > > Yes, that's definitely not matching what rust does. > > Sthen, you probably want to revert that one, rust *does* want gcc4 from > ports currently. > > (the fact it's still using MODULES = gcc4 directly is a tell-tale) > > Semarie, on the other hand, on a clang-based architecture, rust is now > very much on its own. libstdc++ is wildy incompatible with libc++, which > basically means that you can build rust programs, but you can't link with > other C++ based software, and vice-versa.
the current dependence to gcc4 is due to devel/llvm (where I think the WANTLIB changes is wrong too, even if estdc++ isn't missing: the port still have gcc4 in MODULES). $ cd /usr/ports/devel/llvm $ make show=MODULES devel/cmake lang/python gcc4 $ make show=WANTLIB c++ c++abi pthread c m pthread z estdc++>=17 $ make port-lib-depends-check Use of each() on hash after insertion without resetting hash iterator results in undefined behavior at /home/semarie/repos/openbsd/ports/infrastructure/bin/check-lib-depends line 445. llvm-4.0.1p0(devel/llvm,-main): Extra: c++.0 c++abi.0 py-llvm-4.0.1(devel/llvm,-python): Extra: clang.5 rustc uses LLVM libraries. The LLVM libraries are using libestdc++, so rustc *must* use libestdc++. if devel/llvm switches to use clang, a minimal change is require to lang/rust to use it (and use libc++ too). it is the direction that we should take (but please let rust-1.19.0 be pushed in tree before). thanks. -- Sebastien Marie
