Segfault while importing CUE definitions from Istio API definitions

[Niksko]

What version of CUE are you using (cue version)?

$ cue version
cue version v0.5.0

go version go1.20.3
      -buildmode exe
       -compiler gc
       -trimpath true
     CGO_ENABLED 1
          GOARCH amd64
            GOOS darwin
         GOAMD64 v1

Does this issue reproduce with the latest stable release?

Yes

What did you do?

cd $(mktemp -d)
(
set -e
cue mod init
go mod init mod.test
go get istio.io/api/networking/v1beta1@v0.0.0-20230511193058-044e6e6ce64a
cue get go istio.io/api/networking/v1beta1
)

What did you expect to see?

No segfault, and definitions that work.
Interestingly, the definitions are still generated in my cue.mod directory but perhaps I'm missing some?
If I try to make use of a definition by importing them, I get errors:

import failed: import failed: cannot find package "google.golang.org/protobuf/types/known/durationpb":
    ./definitions/routing.cue:7:2
    ./cue.mod/gen/istio.io/api/networking/v1beta1/virtual_service.pb_go_gen.cue:7:8

What did you see instead?

panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x16ff0f9]

goroutine 1 [running]:
cuelang.org/go/cmd/cue/cmd.recoverError(0xc00c4ade90)
	cuelang.org/go/cmd/cue/cmd/root.go:261 +0x7b
panic({0x17aeca0, 0x1e09ee0})
	runtime/panic.go:884 +0x213
cuelang.org/go/cmd/cue/cmd.(*extractor).extractPkg(0xc00a6234d0, {0xc000040054, 0x3f}, 0x0)
	cuelang.org/go/cmd/cue/cmd/get_go.go:438 +0x79
cuelang.org/go/cmd/cue/cmd.(*extractor).extractPkg(0xc00a6234d0, {0xc000040054, 0x3f}, 0xc0000cca80)
	cuelang.org/go/cmd/cue/cmd/get_go.go:554 +0xb1a
cuelang.org/go/cmd/cue/cmd.extract(0xc000354ed0, {0xc000392050, 0x1, 0x1})
	cuelang.org/go/cmd/cue/cmd/get_go.go:417 +0x3e5
cuelang.org/go/cmd/cue/cmd.mkRunE.func1(0xc000388280?, {0xc000392050, 0x1, 0x1})
	cuelang.org/go/cmd/cue/cmd/root.go:72 +0xb3
github.com/spf13/cobra.(*Command).execute(0xc000388280, {0xc000392020, 0x1, 0x1})
	github.com/spf13/cobra@v1.4.0/command.go:856 +0x67c
github.com/spf13/cobra.(*Command).ExecuteC(0xc00036ea00)
	github.com/spf13/cobra@v1.4.0/command.go:974 +0x3bd
github.com/spf13/cobra.(*Command).Execute(...)
	github.com/spf13/cobra@v1.4.0/command.go:902
cuelang.org/go/cmd/cue/cmd.(*Command).Run(0xc000354ed0, {0x3?, 0x3?})
	cuelang.org/go/cmd/cue/cmd/root.go:246 +0x6b
cuelang.org/go/cmd/cue/cmd.mainErr({0x1996288, 0xc00019c008}, {0xc00019a050?, 0x1fa9a68?, 0x60?})
	cuelang.org/go/cmd/cue/cmd/root.go:183 +0x55
cuelang.org/go/cmd/cue/cmd.Main()
	cuelang.org/go/cmd/cue/cmd/root.go:165 +0x7c
main.main()
	cuelang.org/go/cmd/cue/main.go:24 +0x19

This also segfaults on the latest alpha, and segfaults on 0.4.3.

[Niksko]

Possibly related issue, though it doesn't have any details? istio/api#2620

[Niksko]

Apologies, this seems to be a dup of #2046

You can solve the import issue with:

cue get go google.golang.org/protobuf/types/known/durationpb

However at this point, you will realize that the generated definitions of a lot of #SomeDefinition: _, presumably because of the segfault that aborted the above operation.

Would love a workaround if anyone has one.