dockerfile: add delve to binaries-for-test

[crazy-max]

follow-up #5291 (comment)

[crazy-max]

Does not seem supported on freebsd: https://github.com/moby/buildkit/actions/runs/11722197637/job/32651224009?pr=5497#step:5:131

 > [dlv 1/1] RUN --mount=target=/root/.cache,type=cache    --mount=target=/go/pkg/mod,type=cache <<EOT (set -ex...):
0.737 go: downloading golang.org/x/sys v0.13.0
0.741 go: downloading github.com/cpuguy83/go-md2man/v2 v2.0.2
0.742 go: downloading gopkg.in/yaml.v3 v3.0.1
0.784 go: downloading github.com/cilium/ebpf v0.11.0
0.798 go: downloading go.starlark.net v0.0.0-20231101134539-556fd59b42f6
0.866 go: downloading github.com/mattn/go-runewidth v0.0.13
0.907 go: downloading github.com/russross/blackfriday/v2 v2.1.0
0.913 go: downloading github.com/rivo/uniseg v0.2.0
0.990 go: downloading golang.org/x/exp v0.0.0-20230224173230-c95f2b4c22f2
1.126 pkg/mod/github.com/go-delve/[email protected]/service/debugger/debugger.go:32:2: found packages native (dump_freebsd.go) and can_not_build_on_freebsd_with_cgo_disabled (support_sentinel_cgo_freebsd.go) in /go/pkg/mod/github.com/go-delve/[email protected]/pkg/proc/native

Seems we need to enable CGO: https://github.com/go-delve/delve/blob/b16e12fde736f7cad60cfe4d029ba9595ca8de0c/pkg/proc/native/support_sentinel_cgo_freebsd.go#L5

See also go-delve/delve#1480

[thaJeztah]

Seems we need to enable CGO

How much would we loose if we'd skip this for freeBSD? (mostly considering if it's worth adding CGO only for that platform)

[crazy-max]

Seems we need to enable CGO

How much would we loose if we'd skip this for freeBSD? (mostly considering if it's worth adding CGO only for that platform)

Yes I think I will skip freebsd, enabling CGO doesn't seem to work, some headers look missing:

 > [dlv 2/2] RUN --mount=target=/root/.cache,type=cache    --mount=target=/go/pkg/mod,type=cache <<EOT (set -ex...):
0.110 + xx-go install github.com/go-delve/delve/cmd/[email protected]
0.855 # runtime/cgo
0.855 gcc_freebsd_amd64.c:7:10: fatal error: 'sys/signalvar.h' file not found

[profnandaa]

LGTM, thanks for the add.

[tonistiigi]

Why did you change the GOBIN solution?

[crazy-max]

We can't install cross-compiled binaries when GOBIN is set: https://github.com/golang/go/blob/84e58c84fdbe4681b4cbfeb615aaba3437c8ac85/src/cmd/go/internal/work/build.go#L771-L772