> -----Original Message----- > From: Boost-users <boost-users-boun...@lists.boost.org> On Behalf Of DV > Henkel-Wallace via Boost- > users > Sent: 9 July 2020 15:41 > To: Mathias Gaunard <mathias.gaun...@ens-lyon.org> > Cc: DV Henkel-Wallace <gu...@henkel-wallace.org>; boost-users@lists.boost.org > Subject: Re: [Boost-users] Boost ABI/Linkage of clang vs g++ > > > > On Jul 9, 2020, at 04:25, Mathias Gaunard <mathias.gaun...@ens-lyon.org> > > wrote: > > > > On Thu, 9 Jul 2020 at 08:07, DV Henkel-Wallace via Boost-users > > <boost-users@lists.boost.org> wrote: > > > >> We build with clang++-10 w/libc++.a and g++-10 w/libstdc++.a, so > >> build a copy of boost in each configuration as well. This works > >> great on the Mac development machines but the clang case doesn't > >> generate the correct linkage on the Linux deployment machines. The > >> correct clang linkage is std::__1::basic_string... but boost builds > >> with std::__cxx11::basic_string > > > > libc++ is not binary compatible with libstdc++. > > You need to use either libstdc++ or libc++ with both compilers if you > > want binary compatibility. > > > > This doesn't have anything to do with Boost. > > Thanks Mathias. I did not express my problem clearly. This is a b2 issue; I > doubt any _library source > code_ has any direct interaction with this and I'm sorry if I accidentally > gave that impression. Is there a > way to get b2 to disgorge the environment and tool invocation of each step > (basically what is passed to > system() or exec())? > > The background, perhaps clarified: > > We have our own code, some third party code (like Boost) and of course > different runtime platforms > (Mac, iOS, Linux...). Since different platforms use different > compilers/runtimes as their "native" stack, > our development system builds everything end-to-end with both gcc and clang > to catch problems as > early as possible. All compilation is with c++14 or later, post the C++11 > ABI break, hence the naming > issues. This process isolates us from any system libraries that don't have C > linkage. > > Therefore g++ is used to compile libstdc++, boost, other third party code, > and our code. Symbols are > generated that use __c++11:: in their name. > And clang++ is used to compile libc++, boost, other third party code, and our > code. Symbols are > generated that use use __1:: in their name. > > But boost itself is compiled via b2 and what is passed to the compiler (and > which compiler b2 chooses) is > quite opaque. Despite my attempts to force the use of clang it appears that > b2 is either calling g++ or > otherwise asking clang to use g++-style symbol linkage on Linux. On the Mac > the same invocation > behaves as expected. > > I'm compiling boost this way: > > export CC=clang CXX="clang++ -stdlib=libc++" CXXSTD=c++20 ; ./b2 > stdlib=libc++ toolset=clang > boost.locale.icu=off boost.locale.std=off --with-atomic --with-chrono > --with-date_time --with-headers -- > with-locale --with-log --with-program_options --with-random --with-regex > --with-system --with-thread > threading=multi -sNO_COMPRESSION=1 link=static install > > Any thoughts on how to debug this?
Does b2 -debug-configuration help? https://boostorg.github.io/build/manual/master/index.html section 3.3 configuration ☀ You can use the --debug-configuration option to find which configuration files are actually loaded. Paul _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org https://lists.boost.org/mailman/listinfo.cgi/boost-users
