goalng 1.21.0 have error not supper

[pdxrlj]

../../../go/pkg/mod/github.com/lukeroth/gdal@v0.0.0-20230422025444-05e99f726ff9/gdal.go:44:11: cannot define new methods on non-local type C.CPLErr

[chris]

I'm seeing this as well:

❯ go build
# github.com/lukeroth/gdal
../../../../go/pkg/mod/github.com/lukeroth/gdal@v0.0.0-20230422025444-05e99f726ff9/gdal.go:44:11: cannot define new methods on non-local type C.CPLErr
../../../../go/pkg/mod/github.com/lukeroth/gdal@v0.0.0-20230422025444-05e99f726ff9/gdal.go:60:11: cannot define new methods on non-local type C.OGRErr

[paulterinho]

Same here :(

[paulterinho]

@lukeroth Any recommendations about what I might be doing incorrectly? (P.S. great project!)

[chris]

To add a bit more - this started happening after upgrading from Go 1.20 to 1.21. I will also note that this is on macOS (I'm on macOS 13.5), and I'm not sure if other OS's are affected the same way. So, it appears it's something related to use with Go 1.21. I've used this project (agree, great!) for several years now, and with several Go versions, first time I've seen a breakage that I can remember. Going back to Go 1.20.7 alleviated the problem for me.

[paulterinho]

@chris Timely update and advice! Thanks so much. Can confirm, 1.20 works!

[lukeroth]

In the most recent release notes, https://tip.golang.org/doc/go1.21, it says:

Cgo
In files that import "C", the Go toolchain now correctly reports errors for attempts to declare Go methods on C types.

It looks like 1.21 is reporting an error for something that was already incorrect but wasn't caught until now; we will need to wrap the C error types in Go error types here to declare this method.

[lukeroth]

OK, I've wrapped the CPLErr / OGRErr in a Go type to prevent these errors. Builds and passes tests on Go 1.21, GDAL 3.6.4.

[chris]

@lukeroth thanks for the quick fix - verified it resolves the compile errors for me.

[paulterinho]

@lukeroth Agreed with @chris, Thanks for the swift fix!