On Mon, 18 Nov 2019, Maciej W. Rozycki wrote: > > 4. How does this interact with sysroot suffixes (again, this should be > > made clear in the documentation)? > > There is no interaction, the patch merely changes where the libraries are > installed. If the installation sysroot directory chosen is not one known > by the GCC driver, then the newly-installed target libraries won't be > automatically used (that of course can be changed with the appropriate use > of the `-B', `-L' and `--sysroot=' driver options).
Perhaps the "sysroot" phrasing of the option name is confusing. The documentation in install.texi says "@var{dir} rather than @option{$@{gcc_tooldir@}/lib}". If that means, for example, that when "-print-multi-os-directory" prints "../lib64" the libraries are installed in $dir/../lib64 (so you'd pass --with-install-sysroot=/some/where/lib rather than --with-install-sysroot=/some/where), it's definitely not a sysroot. If in fact $dir/lib/../lib64 would be used, the documentation should say so. But even then, if you configure GCC using "--with-sysroot" or "--with-build-sysroot", both of those paths are the top-level sysroot, to which the sysroot suffix gets appended before GCC uses it for any purpose, unless you explicitly build using --no-sysroot-suffix. So I still think it's natural for a user of GCC's configure scripts to expect the new option, like the other sysroot-related configure options, also to be one to which the per-multilib sysroot suffix gets appended before GCC uses it. And if it's not like that, the documentation needs to say so explicitly. -- Joseph S. Myers jos...@codesourcery.com