We use neither --with-sysroot nor --with-build-sysroot. The reason is that, the hard-coded path in GCC repository - that is, the /mingw/ one - does not actually exist.
In order to build GCC for mingw targets, we take either solution: 0) Make a symlink (or rather, a copy, since Windows does not support symlinks) as /mingw/, as mentioned in https://sourceforge.net/p/mingw-w64/wiki2/Native%20Win64%20compiler/ 1) Replace the non-existent path with an existent one, as done in https://github.com/lhmouse/MINGW-packages/blob/master/mingw-w64-gcc-git/PKGBUILD#L112 ------------------ Best regards, lh_mouse 2016-05-10 ------------------------------------------------------------- 发件人：Andrew Pinski <pins...@gmail.com> 发送日期：2016-05-10 05:10 收件人：Brett Neumeier 抄送：lh_mouse,Jonathan Wakely,gcc 主题：Re: Re: GCC 6.1 Hard-coded C++ header paths and relocation problem on Windows On Mon, May 9, 2016 at 1:31 PM, Brett Neumeier <bneume...@gmail.com> wrote: > On Tue, May 3, 2016 at 10:01 AM, lh_mouse <lh_mo...@126.com> wrote: >> Should I file a bug report then? >> We need some Linux testers, though not many people on Linux relocate >> compilers. > > For what it's worth -- I encountered the same problem on a GNU/Linux > system. In my specific situation, I'm cross-compiling GCC using an > AMD64-to-mips64el cross-toolchain, and installing the resulting GCC in > a sysroot directory. When I try to use that GCC on a target device > where (of course) the sysroot directory becomes "/", the hard-coded > "/path/to/sysroot" from the host system is still used to find the C++ > headers, resulting in the same ".../include/c++/6.1.1/cstdlib:75:25: > fatal error: stdlib.h: No such file or directory" error message you > got. > > Changing #include_next to #include in cstdlib and cmath fixed my > problem -- so, thank you very much for this discussion! It helped at > least one other person. > > Please let me know if there's any other testing I can do to help. This sounds like a good use of --with-build-sysroot instead of just --with-sysroot. I use the following for the candian cross: --with-sysroot=/ --with-build-sysroot=${SYSROOT} Thanks, Andrew > > Cheers, > > Brett
