x/build/cmd/golangbuild: possibility of false-negatives in detecting successful command execution

[dmitshur]

I spotted it's sometimes possible for a build to have steps with errors in the log, yet the exit code unexpectedly ended up being 0.

For example, in https://ci.chromium.org/b/8773129168948219089, unchecking "Hide Succeeded Steps" shows the "test golang.org/x/pkgsite module for android/amd64" build step as successful, yet clicking into its output log shows many cgo-related errors like:

 # golang.org/x/pkgsite/devtools/cmd/csphash.test
 loadinternal: cannot find runtime/cgo

It ends with "exiting with 0" as opposed to a non-zero exit code as usual (e.g., this failed step ends with "exiting with 1" as expected).

The problem may be directly in golangbuild itself or in one of the components it was invoking during that build step.

CC @golang/release, @mknyszek.

[dmitshur]

Looks like the bug is in an underlying component, the go command. I can reproduce on a Linux machine with:

$ go version
go version go1.21.0 linux/amd64
$ GOOS=android GOARCH=amd64 go test -json -c -o=/dev/null ./...
go: downloading gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
go: downloading cloud.google.com/go/storage v1.18.2
go: downloading golang.org/x/net v0.13.0
[...]
{"Time":"2023-08-11T17:24:59.434296396Z","Action":"start","Package":"golang.org/x/pkgsite/cmd/frontend"}
{"Time":"2023-08-11T17:24:59.434426674Z","Action":"output","Package":"golang.org/x/pkgsite/cmd/frontend","Output":"?   \tgolang.org/x/pkgsite/cmd/frontend\t[no test files]\n"}
{"Time":"2023-08-11T17:24:59.434466057Z","Action":"skip","Package":"golang.org/x/pkgsite/cmd/frontend","Elapsed":0}
{"Time":"2023-08-11T17:24:59.434803653Z","Action":"start","Package":"golang.org/x/pkgsite/cmd/internal/cmdconfig"}
{"Time":"2023-08-11T17:24:59.43493743Z","Action":"output","Package":"golang.org/x/pkgsite/cmd/internal/cmdconfig","Output":"?   \tgolang.org/x/pkgsite/cmd/internal/cmdconfig\t[no test files]\n"}
[...]
# golang.org/x/pkgsite/internal/vuln.test
loadinternal: cannot find runtime/cgo
# golang.org/x/pkgsite/internal/worker.test
loadinternal: cannot find runtime/cgo
# golang.org/x/pkgsite/internal/testing/integration.test
loadinternal: cannot find runtime/cgo
$ echo $?
0

I'll narrow it down a bit more and file a separate bug for cmd/go. Edit: Filed #62123.

[dmitshur]

We discussed this and plan to let the fix land in the affected component. Nothing to do in golangbuild.