Cross compile

[samsamm777]

Im having issues with cross compiling. Compiling normally on OSX works fine. However when i try the following it produces errors. Any ideas?

$ GOOS=linux go build
# github.com/discordapp/lilliput
../../discordapp/lilliput/lilliput.go:26: undefined: ImageHeader
../../discordapp/lilliput/lilliput.go:41: undefined: Framebuffer
../../discordapp/lilliput/lilliput.go:48: undefined: Framebuffer
../../discordapp/lilliput/ops.go:43: undefined: Framebuffer

Edit:
I get this error when building the deps for osx or linux.

checking for object file format of host system... Mach-O64
checking for object file format specifier (NAFLAGS) ... -fmacho64 -DMACHO -D__x86_64__
checking whether the assembler (nasm -fmacho64 -DMACHO -D__x86_64__) works... no
configure: error: installation or configuration problem: assembler cannot create object files.

[brian-armstrong-discord]

Have you tried brew install nasm?

[samsamm777]

@brian-armstrong-discord Yes I've now got all the deps installed. Initially thought that would fix it, however building with crosscompile still doesn't work.

[brian-armstrong-discord]

What is the error?

[realtruckcgoltz]

I'd like to add my voice to this issue as well. It seems like cross-compiling, regardless of the host os, isn't working as hoped.

On macOS:

$ GOOS=linux go build
# github.com/discordapp/lilliput
../../go/src/github.com/discordapp/lilliput/lilliput.go:26:13: undefined: ImageHeader
../../go/src/github.com/discordapp/lilliput/lilliput.go:41:14: undefined: Framebuffer
../../go/src/github.com/discordapp/lilliput/lilliput.go:48:12: undefined: Framebuffer
../../go/src/github.com/discordapp/lilliput/ops.go:43:16: undefined: Framebuffer

On Linux:

$ GOOS=darwin go build
# github.com/discordapp/lilliput
../../go/src/github.com/discordapp/lilliput/lilliput.go:26:13: undefined: ImageHeader
../../go/src/github.com/discordapp/lilliput/lilliput.go:41:14: undefined: Framebuffer
../../go/src/github.com/discordapp/lilliput/lilliput.go:48:12: undefined: Framebuffer
../../go/src/github.com/discordapp/lilliput/ops.go:43:16: undefined: Framebuffer

go build in the same directory works regardless of platform.

My "go greeness" is showing here, but could it be that the platform is getting lost along the way, resulting in a build attempt that's just all kinds of confused?

[brian-armstrong-discord]

Well, this package also has c deps that are needed, and compilation has to occur with cgo.

Maybe https://gist.github.com/steeve/6905542 is relevant?

[brian-armstrong-discord]

It looks like if nothing else, in cross-compile mode, you need CGO_ENABLED=1. But you'll also need a valid cross-compile setup for compiling the C deps.

[RichardLindhout]

Did you manage to work around this issue @samsamm777

[RichardLindhout]

docker run -it --rm \
  -v $GOPATH/src/github.com/MYPROJECT/app/backend:/go/src/github.com/MYPROJECT/app/backend \
  -w /go/src/github.com/MYPROJECT/app/backend \
  -e CGO_ENABLED=1 \
  docker.elastic.co/beats-dev/golang-crossbuild:1.14.4-main-debian8 \
  --build-cmd "go build" \
  -p "linux/amd64"

[RichardLindhout]

Only this error left now:

/usr/bin/ld: cannot find -lpng
/usr/bin/ld: cannot find -lpng
collect2: error: ld returned 1 exit status
Error: failed building for linux/amd64: exit status 2
failed building for linux/amd64: exit status 2

[RichardLindhout]

docker run -it --rm \
  -v $GOPATH/src/github.com/MYPROJECT/app/backend:/go/src/github.com/MYPROJECT/app/backend \
  -w /go/src/github.com/MYPROJECT/app/backend \
  -e CGO_ENABLED=1 \
  docker.elastic.co/beats-dev/golang-crossbuild:1.14.4-main-debian8 \
  --build-cmd "
  apt-get update
   apt-get install gcc libc6-dev

 apt-get install libx11-dev xorg-dev libxtst-dev libpng++-dev   

 apt-get install xcb libxcb-xkb-dev x11-xkb-utils libx11-xcb-dev libxkbcommon-x11-dev libxkbcommon-dev

 apt-get install xsel xclip
  go build -v" \
  -p "linux/amd64"

Results in

/usr/bin/ld: /go/pkg/mod/github.com/discordapp/lilliput@v0.0.0-20191204003513-dd93dff726a5/deps/linux/lib/libswscale.a(swscale.o): unrecognized relocation (0x2a) in section `.text'
/usr/bin/ld: final link failed: Bad value
collect2: error: ld returned 1 exit status
Error: failed building for linux/amd64: exit status 2
failed building for linux/amd64: exit status 2

[RichardLindhout]

Ah debian8 is old apparently crystal-lang/crystal#8653 (comment). It works with this command on OSX.

docker run -it --rm \
  -v $GOPATH/src/github.com/MYPROJECT/app/backend:/go/src/github.com/MYPROJECT/app/backend \
  -w /go/src/github.com/MYPROJECT/app/backend \
  -e CGO_ENABLED=1 \
  docker.elastic.co/beats-dev/golang-crossbuild:1.14.4-main \
  --build-cmd "
  apt-get -y update
   apt-get -y install gcc libc6-dev

 apt-get -y install libx11-dev xorg-dev libxtst-dev libpng++-dev   

 apt-get -y install xcb libxcb-xkb-dev x11-xkb-utils libx11-xcb-dev libxkbcommon-x11-dev libxkbcommon-dev
apt-get -y upgrade binutils
 apt-get -y install xsel xclip
  go build -v" \
  -p "linux/amd64"

[RichardLindhout]

Final command :-D

It works 👍

docker run -it --rm \
  -v $GOPATH/src/github.com/MYPROJECT/app/backend:/go/src/github.com/MYPROJECT/app/backend \
  -w /go/src/github.com/MYPROJECT/app/backend \
  -e CGO_ENABLED=1 \
  docker.elastic.co/beats-dev/golang-crossbuild:1.14.4-main \
  --build-cmd "
apt-get -y update
apt-get -y install libpng++-dev   
go build -v
" \
  -p "linux/amd64"