ENTRYPOINT w/o argument behaves differently with buildkit

[yamt]

• [x] I have tried with the latest version of Docker Desktop
• [x] I have tried disabling enabled experimental features
• [x] I have uploaded Diagnostics
• Diagnostics ID: 17EAB293-3DF5-4FEE-9400-A16F4036812E/20210325021752

Expected behavior

The same Dockerfile produces reasonably compatible images with and without buildkit

Actual behavior

It produces incompatible images.

Information

• macOS Version: 10.14.6
• Docker Desktop Version: 3.2.2

Steps to reproduce the behavior

run test.sh script found in https://github.com/yamt/garbage/tree/master/docker-empty-entrypoint i put results on my environment here https://github.com/yamt/garbage/tree/master/docker-empty-entrypoint/results i disabled buildkit following the instruction here https://docs.docker.com/docker-for-mac/release-notes/#docker-desktop-320

[stephen-turner]

Thanks for the report, moving to buildx repository.

[tonistiigi]

What version of docker? Or buildx container if you use that.

[yamt]

@tonistiigi i was using whatever versions bundled with docker desktop for mac 3.2.2. docker version looks like the following.

Client: Docker Engine - Community
 Cloud integration: 1.0.9
 Version:           20.10.5
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        55c4c88
 Built:             Tue Mar  2 20:13:00 2021
 OS/Arch:           darwin/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.5
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       363e9a8
  Built:            Tue Mar  2 20:15:47 2021
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.3
  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b
 runc:
  Version:          1.0.0-rc92
  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0