build-arg failed to pass buildx in buildx 0.29.1 and 0.30.0

[jackliusr]

Contributing guidelines

• I've read the contributing guidelines and wholeheartedly agree

I've found a bug and checked that ...

• ... the documentation does not mention anything about my problem
• ... there are no open or closed issues that are related to my problem

Description

--build-arg BASE_IMAGE=vsc-test-ca279a04850f03af65f95e2c8a764eaff03d3cf084cc1094d0d97ceb2c5bc03e

ARG BASE_IMAGE
FROM $BASE_IMAGE

Workaround: add "# syntax=docker/dockerfile:1.4" as the first line in my Dockerfile

Expected behaviour

no warning " - InvalidDefaultArgInFrom: Default value for ARG $BASE_IMAGE results in empty or invalid base image name " and the build arg is correctly passed into buildkit

Actual behaviour

InvalidDefaultArgInFrom: Default value for ARG $BASE_IMAGE results in empty or invalid base image name

Buildx version

0.29.1,0.30.0

Docker info

Builders list

NAME/NODE     DRIVER/ENDPOINT   STATUS    BUILDKIT   PLATFORMS
default*      docker
 \_ default    \_ default       running   v0.25.2    linux/amd64 (+3)

Configuration

ARG BASE_IMAGE
FROM $BASE_IMAGE

Build logs

Additional info

No response