all: cleanup ineffectual //go:linkname directives

[mdempsky]

There are a lot of //go:linkname directives in macOS packages that don't do anything. We should remove them.

To elaborate, a directive like //go:linkname foo bar sets the Go variable or function named foo to use bar as its linker symbol (instead of mypkgpath.foo, like it would normally use). But if there's no Go variable or function named foo, it just silently doesn't do anything.

In CL 273986 (2d6ff99), I removed the occurrences within the standard library, but there are more in the vendored x/sys package that need to be fixed. There might be more instances in other repos too.

To test for problems, you can checkout the dev.regabi branch; revert CL 274732 (42e46f4); and then build packages like golang.org/x/sys/unix w/ various GOOS/GOARCH combinations.

[gopherbot]

Change https://golang.org/cl/274732 mentions this issue: [dev.regabi] cmd/compile: comment out //go:linkname warning

[gopherbot]

Change https://golang.org/cl/274573 mentions this issue: unix: remove ineffectual //go:linkname directives

[ianlancetaylor]

Is there more to do here? Are we going to do anything further for the 1.17 release?

[dmitshur]

We're three weeks into the release freeze now. It seems this is either mostly done, or if there's more to do, progress can be continued in a future Go release, so I'll move it to Backlog. @mdempsky Please feel free to update the issue as needed.

[cuonglm]

@mdempsky seems we can close this issue now?

[Ebi-web]

ping