On Thu, Mar 31, 2016 at 11:50 AM, Patrick Boettcher via cfe-users <cfe-users@lists.llvm.org> wrote: > Hi, > > On Thu, 24 Mar 2016 16:48:30 +0100 > Arnaud Allard de Grandmaison <arnaud.ad...@gmail.com> wrote: > >> Hi Patrick, >> >> This is a common case when cross compiling, so clang knows how to use >> a gcc-toolchain installation: you just have to pass it the >> "--sysroot=..." and "--toolchain=..." arguments, and it will get the >> header files and linker / assembler for your target --- assuming your >> gcc-toolchain has a standard layout. > > I'm getting back to you after (some vacations and) having compared > linaro's latest toolchain to the one I built. > > Linaro provides a sysroot-package which does not contain > c++-header-files. Instead they are located in the gcc-package, as in > my package, in > > <target>/include/c++/<gcc-version>/ > > I'm unable to convince clang(++) to include this search-dir using any > combination of the following options with variations on the path name. > > --gcc-toolchain= > -B > --sysroot= > > sysroot works a little bit, but only for c-include which are located in > <sysroot-dir>/usr/include. > > Using gcc-linaro-5.3-2016.02-x86_64_aarch64-elf I would highly > appreciate an example of how to invoke clang++ for cross-compilation > with this gcc and its includes? > > My current try is: > > TARGET=aarch64-elf \ > GCC_ROOT=~/Downloads/gcc-linaro-5.3-2016.02-x86_64_aarch64-elf \ > ~/devel/upstream/build/bin/clang++ \ > -v \ > --target=$TARGET \ > --gcc-toolchain=$GCC_ROOT/$TARGET \ > --sysroot=$GCC_ROOT/$TARGET/sysroot \ > -nostdlib \ > -o testCCompiler.cpp.obj -c \ > -std=c++11 \ > test.cpp > > test.cpp is empty except #include <cstdint> which it doesn't find. > > Linaro's gcc has all include paths in its search list. > > Thanks in advance for any help,
We found Ubuntu (perhaps Debian) broke the cross-compile using --sysroot some time ago. Also see "g++-arm-linux-gnueabi cannot compile a C++ program with --sysroot", https://bugs.launchpad.net/ubuntu/+source/gcc-defaults-armel-cross/+bug/1375071. We were working around the broken C++ header includes by specifically calling them out with -I. See the comment "Fix C++ header paths for Ubuntu" at https://github.com/weidai11/cryptopp/blob/master/setenv-embedded.sh#L96. ARM's "GCC ARM Embedded Tools" works as expected. Its maintained by ARM employees. Also see the PPA at https://launchpad.net/gcc-arm-embedded. Since the time of the Launchpad bug report, the linker no longer works, either. Jeff _______________________________________________ cfe-users mailing list cfe-users@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-users