compile: invalid value "go1.21.7" for -lang: should be something like "go1.12"

[jasonwbarnett]

Describe the bug
When I had the following go.mod

module domain.com/package/path

go 1.21.7

require github.com/pelletier/go-toml v1.9.5

compiling the program via pants failed with this error:

compile: invalid value "go1.21.7" for -lang: should be something like "go1.12"

After updating the go.mod to this it worked:

module domain.com/package/path

go 1.21

require github.com/pelletier/go-toml v1.9.5

Pants version
2.21.0.dev3

OS
Mac OS

[tgolsson]

Looked like #20677 but I think this is different. Likely fall-out from that.

[tdyas]

We probably need to make sure we only pass go1.X as a value to the -lang parameter.

[tdyas]

The relevant part of the code is

pants/src/python/pants/backend/go/util_rules/build_pkg.py

Lines 716 to 720 in 3200ee3

	# See https://github.com/golang/go/blob/f229e7031a6efb2f23241b5da000c3b3203081d6/src/cmd/go/internal/work/gc.go#L79-L100
	# for where this logic comes from.
	go_version = request.minimum_go_version or "1.16"
	if go_root.is_compatible_version(go_version):
	compile_args.extend(["-lang", f"go{go_version}"])

.

[jasonwbarnett]

The relevant part of the code is

pants/src/python/pants/backend/go/util_rules/build_pkg.py

Lines 716 to 720 in 3200ee3

	# See https://github.com/golang/go/blob/f229e7031a6efb2f23241b5da000c3b3203081d6/src/cmd/go/internal/work/gc.go#L79-L100
	# for where this logic comes from.
	go_version = request.minimum_go_version or "1.16"
	if go_root.is_compatible_version(go_version):
	compile_args.extend(["-lang", f"go{go_version}"])

.

Thanks. I'll try to post a fix in the next few days.

[bndabbs]

This looks like the error reported in golang/go#66553.

Is it possible that Pants is caching golang.org/x/tools/gopls somewhere? If so then maybe the fix should be to install gopls using the resolved go_version?

[tdyas]

This looks like the error reported in golang/go#66553.

Is it possible that Pants is caching golang.org/x/tools/gopls somewhere? If so then maybe the fix should be to install gopls using the resolved go_version?

Pants does not use gopls at all. The linked source files are the likely culprit since they generate the actual -lang parameter passed to the Go toolchain.

[11xor6]

Does anyone have another work around in the meantime while we wait for the patch? Modifying my go.mod file doesn't fix this for me on both pants versions 2.21.0 and 2.22.0. Locally I'm running Go 1.23.2 and my go.mod file has go 1.22 (previously go 1.22.0) and I've tried [golang].minimum_expected_version of 1.22, 1.22.0, 1.23, and 1.23.0.