go:embed disallows using symlinked files by design.
crypto/elliptic is the first std package to use it as of CL 380475,
and unfortunately that broke the TestRepeatBootstrap long test.
The reason it uses symlinks is for speed; it wants to copy GOROOT/src,
but regular files aren't going to be modified in any way,
so a symlink, if supported, means not needing to copy the contents.
Replace the symlink attempt with hard links,
which will mean regular files remain as such, fixing go:embed.
It's worth noting that on many systems hard links won't work,
as the temporary filesystem tends to be separate,
but it doesn't hurt to try.
In my system, where /tmp is tmpfs, the test now copies more bytes.
With the added Logf, I can see overlayDir goes from ~30ms to ~100ms.
This makes sense, as GOROOT/src currently weighs around 100MiB.
To alleviate that slow-down, stop copying testdata directories,
as they currently weigh around 20MiB and aren't needed for the test.
This gets overlayDir on my system down to an acceptable ~70ms.
I briefly considered teaching overlayDir what files can be symlinks,
but that seemed fairly complex long-term, as any file could be embedded.
While here, start using testing.T.TempDir and fs.WalkDir.
For #50995.
Change-Id: I17947e6bdee96237e1ca0606ad0b95e7c5987bc1
Reviewed-on: https://go-review.googlesource.com/c/go/+/383995
Trust: Daniel Martí <mvdan@mvdan.cc>
Trust: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This test is slow and resource-intensive, and will rarely catch
failures. It is important to run sometimes, but probably a waste of
time on smaller (and especially reverse) builders.
Rather than hard-coding a list of small builders, only run it on the
longtest builders.
Fixes#35233Fixes#30892Fixes#49753
Change-Id: I25a9702e1f541246ea200fd7c79414ca5f69edae
Reviewed-on: https://go-review.googlesource.com/c/go/+/366538
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Update references missed in CL 263142.
For #41190
Change-Id: I778760a6a69bd0440fec0848bdef539c9ccb4ee1
GitHub-Last-Rev: dda42b09ff
GitHub-Pull-Request: golang/go#42874
Reviewed-on: https://go-review.googlesource.com/c/go/+/273946
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Cherry Zhang <cherryyz@google.com>
