Date: Tue, 21 Jun 2011 23:31:43 +0200 From: Damjan Marion <damjan.marion@gmail.com> To: Warner Losh <imp@bsdimp.com> Cc: toolchain@FreeBSD.org Subject: Re: cross-compiling for arm with clang Message-ID: <932DB8CA-22DA-495F-89AC-F547146780B6@gmail.com> In-Reply-To: <AC8BF81A-2EF4-48FF-ABDE-E928C1B4A06E@bsdimp.com> References: <D0F647ED-4AB2-4A61-AD37-423F0AF9805D@gmail.com> <C29B8240-9D19-46CC-A1FC-1B9150547B1D@bsdimp.com> <15B76B64-D26E-420D-AE37-B52A694CDF98@gmail.com> <BF24BE90-48B7-48A0-90FE-234C28AE9CA9@bsdimp.com> <8E65FA9C-330B-4055-8959-75EE06E557E8@gmail.com> <AC8BF81A-2EF4-48FF-ABDE-E928C1B4A06E@bsdimp.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Jun 21, 2011, at 7:06 PM, Warner Losh wrote: >=20 > On Jun 21, 2011, at 3:12 AM, Damjan Marion wrote: >>=20 >> On Jun 17, 2011, at 9:16 PM, Warner Losh wrote: >>>=20 >>> How it normally works is that we build a compiler that invokes the = right as, ld, etc for the architecture in question. Clang is clearly = broken here in assuming that as can cope with anything other than native = assembler :) We normally either build gcc that knows where to find = these files. In the buildworld case, this is communicate with weird = paths and shell variables. With the whole 'xdev' series of targets = (which are instructive to look at), we build into a specific location = /usr/freebsd-xdev-arm/bin, etc). >>>=20 >>> It works by accident for i386 on amd64, I think. as treats the more = or less as the same. >>=20 >> I submitted a patch[1] to clang mailer which invokes = xxx-yyy-zzz-as/ld based on -ccc-host-triple. Patch is copy of netbsd = code which is already in clang. >>=20 >> For me it works well, even when I use clang on Darwin host, it calls = proper as/ld. >>=20 >> # /opt/llvm/bin/clang -ccc-host-triple arm-unknown-freebsd = -mfloat-abi=3Dsoft test.c -o test -v -c >> clang version 3.0 (http://llvm.org/git/clang.git = 98138cdfdee05c0afbab2b209ce8cfe4a52474e1) >> Target: arm-unknown-freebsd >> Thread model: posix >> [snip] >> End of search list. >> "/opt/llvm/bin/arm-unknown-freebsd-as" -o test = /var/folders/kb/kbDaYaFqFQaCg3mXbTLH5U+16gE/-Tmp-/cc-RMHOwf.s >>=20 >>=20 >> Is this what we need to support cross-compiling freebsd with clang? >=20 > As we do it today? No. Today we build the binaries as 'as' which are = part of the buildworld. These binaries aren't called = arm-unknown-freebsd-as, but instead 'as'. >=20 > Do we want to switch? Maybe. Seems that clang will first try to run as/ld which is in the same = directory like clang. That is exactly what we have in /usr/obj/.../bin = so seems that buildworld should work out of the box. Problem with ARM is that clang is not build as part of cross-tools, so = clang from /usr/bin is called instead which also means that as/ld from = /usr/bin are used. --- share/mk/bsd.own.mk (revision 223366) +++ share/mk/bsd.own.mk (working copy) @@ -415,7 +415,7 @@ __T=3D${MACHINE_ARCH} .endif # Clang is only for x86 and 32-bit powerpc right now, by default. -.if ${__T} =3D=3D "amd64" || ${__T} =3D=3D "i386" || ${__T} =3D=3D = "powerpc" +.if ${__T} =3D=3D "amd64" || ${__T} =3D=3D "i386" || ${__T} =3D=3D = "powerpc" || ${__T} =3D=3D "arm" __DEFAULT_YES_OPTIONS+=3DCLANG .else Unfortunately this doesn't mean that cross-compiling works fine now for = ARM. It fails on building lib/libcompiler_rt. Here is output if anybody have idea how to fix it: = http://pastebin.com/Ly2jARjd Damjan
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?932DB8CA-22DA-495F-89AC-F547146780B6>