Initialise workers' label maps before assigning.
Otherwise:
panic: assignment to entry in nil map
goroutine 1 [running]:
main.applyOCIFlags(0xc4200e71e0, 0xc420400000, 0x0, 0x0)
/go/src/github.com/moby/buildkit/cmd/buildkitd/main_oci_worker.go:97 +0x1ac
main.ociWorkerInitializer(0xc4200e71e0, 0xc4204104e0, 0xc420400000, 0x43409b, 0x12, 0xc42026b0f8, 0x4337fc, 0xc420000180)
/go/src/github.com/moby/buildkit/cmd/buildkitd/main_oci_worker.go:118 +0x50
main.newWorkerController(0xc4200e71e0, 0xc4204104e0, 0xc420400000, 0xc420422000, 0xe5dc54, 0x11)
/go/src/github.com/moby/buildkit/cmd/buildkitd/main.go:520 +0x324
main.newController(0xc4200e71e0, 0xc420400000, 0x1c0, 0x0, 0x0)
/go/src/github.com/moby/buildkit/cmd/buildkitd/main.go:489 +0xdc
main.main.func3(0xc4200e71e0, 0x0, 0x0)
/go/src/github.com/moby/buildkit/cmd/buildkitd/main.go:203 +0x3dd
github.com/moby/buildkit/vendor/github.com/urfave/cli.HandleAction(0xcdd420, 0xe93e98, 0xc4200e71e0, 0xc4200e71e0, 0xc42026b888)
/go/src/github.com/moby/buildkit/vendor/github.com/urfave/cli/app.go:502 +0xc8
github.com/moby/buildkit/vendor/github.com/urfave/cli.(*App).Run(0xc4201b6540, 0xc4200300a0, 0xa, 0xa, 0x0, 0x0)
/go/src/github.com/moby/buildkit/vendor/github.com/urfave/cli/app.go:268 +0x60c
main.main()
/go/src/github.com/moby/buildkit/cmd/buildkitd/main.go:238 +0xc64
Also add some random labels to the integration sandbox (which I have confirmed
is enough to trigger this issue before the fix).
Signed-off-by: Ian Campbell <ijc@docker.com>
7cb70e1c31