Golang cmd/go: mod edit: missing -droptoolchain flag

Go version

go version go1.24.3 linux/amd64

Output of go env in your module/workspace:

n/a

What did you do?

'go get -u ' resulted in automatically adding a toolchain line to go.mod

I wanted to remove it again, using 'go mod edit' so the update and follow-up were reproducible as a CLI command for later re-use.

What did you see happen?

'go mod edit' has flags to do almost any other transformation of a go.mod you might want, including '-toolchain' for adding a toolchain. Pretty much every other flag has a '-dropXXX' equivalent.

What did you expect to see?

But '-droptoolchain' is missing.

Comment From: gabyhelp

Related Issues

• cmd/go: compile error for "toolchain default" in go.mod, removed by mod tidy #73127
• go mod tidy removes the toolchain directive #64039 (closed)

Related Documentation

• Command go > Edit go.mod from tools or scripts
• Command go > Edit go.mod from tools or scripts

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Comment From: mknyszek

CC @golang/command-line

Comment From: gopherbot

Change https://go.dev/cl/674075 mentions this issue: cmd/go: mod edit: add -droptoolchain flag

Comment From: matloob

go mod edit is mainly intended to be used by tools. For users, the way to remove the toolchain directive is go get toolchain@none. Maybe we should improve the documentation about this?

Comment From: matloob

I should also add that in Go 1.25, the go command will add the toolchain line in fewer instances. Running go get -u won't add a toolchain directive.