x/mobile: gomobile fails with linker error

[axet]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version go1.10 darwin/amd64

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

GOARCH="amd64"

What did you do?

trying to compile https://gitlab.com/axet/libtorrent with following error

# github.com/anacrolix/go-libutp
/var/folders/lv/m63vrmx5375dgk4jhc05ww000000gn/T/go-build072150581/b125/_x008.o(.ARM.extab+0x0): error: undefined reference to '__gxx_personality_v0'
/var/folders/lv/m63vrmx5375dgk4jhc05ww000000gn/T/go-build072150581/b125/_x008.o(.ARM.extab+0x38): error: undefined reference to '__gxx_personality_v0'
/var/folders/lv/m63vrmx5375dgk4jhc05ww000000gn/T/go-build072150581/b125/_x008.o(.ARM.extab+0x64): error: undefined reference to '__gxx_personality_v0'
/var/folders/lv/m63vrmx5375dgk4jhc05ww000000gn/T/go-build072150581/b125/_x008.o(.ARM.extab+0x9c): error: undefined reference to '__gxx_personality_v0'
clang++: error: linker command failed with exit code 1 (use -v to see invocation)

My first guess this is gomobile issues. According to https://stackoverflow.com/questions/6045809 here something wrong with -lstdcpp definition.

Adding #cgo LDFLAGS: -lstdc++ to the https://github.com/anacrolix/go-libutp/blob/master/utp.go does not solve the issue.

[eliasnaur]

It seems the library doesn't build:

$ CGO_ENABLED=1 CC=<ndk>/clang CXX=<ndk>/clang++ GOOS=android GOARCH=arm go get -u gitlab.com/axet/libtorrent 
# gitlab.com/axet/libtorrent
../dev/go/src/gitlab.com/axet/libtorrent/files.go:52:27: too many arguments in call to t.Files
	have (string)
	want ()
../dev/go/src/gitlab.com/axet/libtorrent/files.go:72:26: t.PieceBytesCompleted undefined (type *torrent.Torrent has no field or method PieceBytesCompleted)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:73:13: t.PieceLength undefined (type *torrent.Torrent has no field or method PieceLength, but does have torrent.pieceLength)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:77:14: t.PieceBytesCompleted undefined (type *torrent.Torrent has no field or method PieceBytesCompleted)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:77:39: t.PieceLength undefined (type *torrent.Torrent has no field or method PieceLength, but does have torrent.pieceLength)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:77:58: t.PieceBytesCompleted undefined (type *torrent.Torrent has no field or method PieceBytesCompleted)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:77:83: t.PieceLength undefined (type *torrent.Torrent has no field or method PieceLength, but does have torrent.pieceLength)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:258:10: t.GetPendingPieces undefined (type *torrent.Torrent has no field or method GetPendingPieces)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:301:3: t.UpdatePiecePriorities undefined (type *torrent.Torrent has no field or method UpdatePiecePriorities, but does have torrent.updatePiecePriorities)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:353:9: t.PieceLength undefined (type *torrent.Torrent has no field or method PieceLength, but does have torrent.pieceLength)
../dev/go/src/gitlab.com/axet/libtorrent/files.go:353:9: too many errors

[axet]

I probably should create simple cpp project to test 'undefined reference', 'dev' branch compiles. Since goland does not support version control for imported code those are common complications build success or failed...

I guess you can just run:

 gomobile bind -o "libtorrent.aar" github.com/anacrolix/go-libutp

[gopherbot]

Change https://golang.org/cl/99875 mentions this issue: cmd/gomobile: drop init step for build and bind commands