On 10 March 2017 at 13:36, Steven Newbury <st...@snewbury.org.uk> wrote: > On Fri, 2017-03-10 at 12:11 +0000, Emil Velikov wrote: >> On 9 March 2017 at 14:39, Steven Newbury <st...@snewbury.org.uk> >> wrote: >> > Introduction of zlib compression for the shader cache means >> > zlib needs to be explicitly linked to libOSMesa and libstandalone >> > otherwise build fails when LTO is used. >> > --- >> >> How exactly are you doing the LTO build ? > I build everything LTO, except for a short blacklist where > unsupportable. Specifically, on this system my global *FLAGS contain > "-flto=8 -fuse-linker-plugin". I have the lto linker plugin symlinked > into "/usr/$CHOST/binutils-bin/lib/bfd-plugins/". > > I also have have the following env vars set to ensure they are called > with the LTO plugin: > AR="gcc-ar" > NM="gcc-nm" > RANLIB="gcc-ranlib" > One should not need these. Have you checked that the issue is reproducible w/o them ?
> Mesa is not blacklisted, and with the patch, and previous to the > compressed shader cache built fine, but otherwise there are undefined > zlib symbols. >> >> The only user of ZLIB is libmesautil.la which in itself uses >> ZLIB_LIBS. > It does, and that seems to satisfy linking of libmesautil.la, but it > doesn't result in the archive containing a static zlib since you're > using "-lz" (at least with the output of pkg-config --libs zlib here) > not explicitly linking to libz.a. (My understanding.) > Can you compare (list here) the link line (make V=1) for the affected objects with and w/o LTO ? There should be -lz in the former case, at least. >> Hence as-is patch looks wrong/incomplete, although I might be missing >> something ? > I guess that depends upon your point of view. To me it's the preferred > behaviour to use the system provided dynamic zlib to resolve the > symbols at load time. We have multiple places that use libmesautil and adding zlib to only some _is_ incomplete. Not to mention that in the OSMesa case - there's nothing in there that uses libmesautil or zlib directly or not, afaict. Hence 'being wrong'. If there's a bug somewhere, hence the need for ZLIB_LIBS, that should be clearly documented alongside the patch. Thanks Emil _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
