Hello Hugo, You are correct, what I try is to cross-compile a go application (in this case Mender client) for the ppc platform (e500 on a MFC8555 processor). 1. I used crosstool-ng instead of buildroot. It has support for "go" as experimental language and as result a gccgo compiler is build and also a libgo library. 2. The mender client is normally build with: go build client_dir what I do is: env GOOS=linux GOARCH=ppc go build -compiler gccgo client_dir Than go complains as explained that ppc is a not supported architecture. Unfortunately the crosstool-ng tooling thus not deliver a new go. I read somewhere that recompiling go with a gccgo compiler might solve this. (so besides the ppc version of ggcgo I also used crosstool-ng to build an x86_64 (amd64) version. 3. Interesting approach, I don't completely understand it yet but will investigate it further.
Is it possible to use a Makefile approach with gccgo instead of go build? On Tuesday, October 20, 2020 at 9:52:17 AM UTC+2 hugo.c...@essensium.com wrote: > > > Hi Gerrit, > > If I understand correctly, I believe you try to cross-compile Go > applications to the PowerPC e500 architecture and as a first step you are > porting Go to this architecture. > > We recently ported Go applications such as Docker and its tools to > architectures not supported by upstream Go, but with an approach quite > different from yours (if I understood well). > > The procedure we follow, is: > > 1. Build the gccgo cross-toolchain with Buildroot: Buildroot currently > builds a toolchain by first building a gcc-initial, then proceeding to > build a gcc-final. We had to insert a new gcc compilation stage before > gcc-final can build the gccgo cross-compiler. This additional gcc > compilation stage makes go-tools available in the native environment that > are required for building the gccgo cross-compiler tools when gcc-final is > built. If I understand well this may be an important part of the solution > to your problem. > > 2. Patch the Buildroot environment to invoke gccgo as the compiler, rather > than gc, for compiling Go applications. We are planning to upstream this > and the previous step to Buildroot in the coming months. > > 3. Implement Go system call bindings: The sys package of the Go runtime > implements system call bindings as part of gccgo (so part of gcc-final), > the golang-sys/unix package is (can be) shipped in the folder > golang-sys/unix of the application you want to build (this is Docker and > tools in our case). The golang-sys package needs to be patched in each > application to produce correct system call bindings for your target > environment (so the PowerPC e500 in your case). Most of our development > time was spent in this last step (it is tricky). > > Using this procedure we have ported Docker and its dependencies and tools > to several ppc 32 bit architectures. > > I hope this helps. > > Hugo > > > > On Tue, Oct 20, 2020 at 6:20 AM gerritbinnenmars <gerritbi...@gmail.com> > wrote: > >> Hello Ian, >> Thanks for the quick reaction. It seems my request was not clear. >> What I am doing is the other way around: using gccgo to build the "go" >> cmd. >> So clone the "go" source from github and then go build -compiler gccgo >> ./cmd/go >> >> Gerrit >> >> -------- Oorspronkelijk bericht -------- >> Van: Ian Lance Taylor <ia...@golang.org> >> Datum: 20-10-20 04:25 (GMT+01:00) >> Aan: Gerrit Binnenmars <gerritbi...@gmail.com> >> Cc: golang-nuts <golan...@googlegroups.com> >> Onderwerp: Re: [go-nuts] gccgo problem compiling go from source >> >> On Mon, Oct 19, 2020 at 2:06 PM Gerrit Binnenmars >> <gerritbi...@gmail.com> wrote: >> > >> > I used crosstool-ng successfully to build a go compiler for ppc e500. >> > Unfortunately go build does not support ppc therefore go needs to be >> > build from source using the amd64 gccgo compiler that I also build >> > with crosstool-ng. >> > >> > Compiling go from source fails: >> > Problem: undefined name stdpkg in internal/goroot/gccgo.go >> > >> > I included the output of my build script below. Any help or tips are >> welcome. >> > >> > With kind regards, >> > >> > Gerrit Binnenmars >> > >> > Info: >> > This is crosstool-NG version 1.24.0.191_364ed7a >> > GO111MODULE="" >> > GOARCH="amd64" >> > GOBIN="" >> > GOCACHE="/home/maintain/.cache/go-build" >> > GOENV="/home/maintain/.config/go/env" >> > GOEXE="" >> > GOFLAGS="" >> > GOHOSTARCH="amd64" >> > GOHOSTOS="linux" >> > GOINSECURE="" >> > GOMODCACHE="/home/maintain/gonew/pkg/mod" >> > GONOPROXY="" >> > GONOSUMDB="" >> > GOOS="linux" >> > GOPATH="/home/maintain/gonew" >> > GOPRIVATE="" >> > GOPROXY="https://proxy.golang.org,direct"; >> > >> GOROOT="/home/maintain/x-tools/x86_64-e500-linux-gnu/x86_64-e500-linux-gnu/sysroot/lib" >> > GOSUMDB="sum.golang.org" >> > GOTMPDIR="" >> > >> GOTOOLDIR="/home/maintain/x-tools/x86_64-e500-linux-gnu/x86_64-e500-linux-gnu/sysroot/lib/pkg/tool/linux_amd64" >> > GCCGO="/home/maintain/x-tools/x86_64-e500-linux-gnu/bin/gccgo" >> > AR="ar" >> > CC="/home/maintain/x-tools/x86_64-e500-linux-gnu/bin/gcc" >> > CXX="/home/maintain/x-tools/x86_64-e500-linux-gnu/bin/g++" >> > CGO_ENABLED="1" >> > GOMOD="" >> > >> CGO_CFLAGS="--with-sysroot=/home/maintain/x-tools/x86_64-e500-linux-gnu/x86_64-e500-linux-gnu/sysroot" >> > CGO_CPPFLAGS="" >> > CGO_CXXFLAGS="-g -O2" >> > CGO_FFLAGS="-g -O2" >> > CGO_LDFLAGS="-g -O2" >> > PKG_CONFIG="pkg-config" >> > GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 >> > -fdebug-prefix-map=/tmp/go-build355977706=/tmp/go-build >> > -gno-record-gcc-switches" >> > go version go1.15.2 linux/amd64 >> > gccgo (GCC) 10.2.0 >> > Copyright (C) 2020 Free Software Foundation, Inc. >> > This is free software; see the source for copying conditions. There is >> NO >> > warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR >> PURPOSE. >> > >> > WORK=/tmp/go-build273889551 >> > mkdir -p $WORK/b100/ >> > cd $WORK >> > /home/maintain/x-tools/x86_64-e500-linux-gnu/bin/gccgo >> > -fgo-importcfg=/dev/null -c -x c - -o /dev/null || true >> > cd /home/maintain/gonew/src/internal/goroot >> > /home/maintain/x-tools/x86_64-e500-linux-gnu/bin/gccgo -c -g -m64 >> > -fdebug-prefix-map=$WORK=/tmp/go-build -gno-record-gcc-switches >> > -fgo-pkgpath=internal/goroot -o $WORK/b100/_go_.o -I >> > $WORK/b100/_importcfgroot_ ./gccgo.go >> > mkdir -p $WORK/b027/ >> > mkdir -p $WORK/b027/_importcfgroot_/cmd/go/internal >> > ln -s >> /home/maintain/.cache/go-build/ad/ade44815e7af8b7305b2db4099ec5b08aafcbd6e374a2c13d8e99c2986ca93c6-d >> > $WORK/b027/_importcfgroot_/cmd/go/internal/libauth.a >> > ln -s >> /home/maintain/.cache/go-build/d2/d26f05f163d86aecfadfbb952dfef9a314aa1c84c23fddd39bce127ccc85d101-d >> > $WORK/b027/_importcfgroot_/cmd/go/internal/libcfg.a >> > mkdir -p $WORK/b027/_importcfgroot_/cmd/internal >> > ln -s >> /home/maintain/.cache/go-build/2f/2f6811b0804c481edbfd9952d1aac22414f84ee1aec229218b03956bf3f9aa7a-d >> > $WORK/b027/_importcfgroot_/cmd/internal/libbrowser.a >> > cd /home/maintain/gonew/src/cmd/go/internal/web >> > /home/maintain/x-tools/x86_64-e500-linux-gnu/bin/gccgo -c -g -m64 >> > -fdebug-prefix-map=$WORK=/tmp/go-build -gno-record-gcc-switches >> > -fgo-pkgpath=cmd/go/internal/web -o $WORK/b027/_go_.o -I >> > $WORK/b027/_importcfgroot_ ./api.go ./http.go ./url.go ./url_other.go >> > # internal/goroot >> > src/internal/goroot/gccgo.go:24:10: error: reference to undefined name >> 'stdpkg' >> > 24 | return stdpkg[path] >> > | ^ >> > # cmd/go/internal/web >> > src/cmd/go/internal/web/api.go:92:45: error: reference to undefined >> > field or method 'Redacted' >> > 92 | return nil, fmt.Errorf("reading %s: %v", u.Redacted(), err) >> >> It looks like you are using the "go" program to build the gccgo >> standard library. That doesn't work. The gccgo standard library must >> be built as part of GCC, using the usual configure/make commands used >> to build GCC itself. When configuring GCC, use --enable-languages=go. >> >> Ian >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/5f8e657e.1c69fb81.3e6dc.0cf4%40mx.google.com >> >> <https://groups.google.com/d/msgid/golang-nuts/5f8e657e.1c69fb81.3e6dc.0cf4%40mx.google.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/7ef29078-6460-4b02-a4ff-94e780fd85f3n%40googlegroups.com.
