9f5e43aeb915e449847095ed4688adf6b28b4f6a

build-9f5e43aeb915e449847095ed4688adf6b28b4f6a

Revert "[tailscale1.18] Revert "cmd/cgo: add go:notinheap annotation …

860e090eddf9534f370c6d9938afe8c0bb2c1fce

build-860e090eddf9534f370c6d9938afe8c0bb2c1fce

[tailscale1.18] Revert "cmd/cgo: add go:notinheap annotation to Windo…

0d07ed810abafea4d6558343b93654eba4126e48

[tailscale1.18] cmd/dist: support embedding of toolchain rev by env var

Git checkouts are not reproducible (in particular, the .git directory's hashes
vary according to the moods of git re: packing and other local settings), so
building our Go toolchain via Nix leads to source hashes that change from machine
to machine and over time.

Since Nix already knows the exact git revision it's building from, this change
lets Nix provide that hash to cmd/dist directly, skipping the rooting around in
.git to find the right hash.

Signed-off-by: David Anderson <[email protected]>

dce70b6d327c7a30b81701f4cc134b56c4e6c229

build-dce70b6d327c7a30b81701f4cc134b56c4e6c229

[release-branch.go1.17] Merge remote-tracking branch 'origin/release-…

fd6b85b80f5fbbfaddef34e7ab6ac83384c50e4d

build-fd6b85b80f5fbbfaddef34e7ab6ac83384c50e4d

[release-branch.go1.17] Merge remote-tracking branch 'origin/release-…

25fe91a25c9630a50138a135105af19ae7c7c3e7

[tailscale1.17] bufio: add Writer.AvailableBuffer

This adds a new Writer.AvailableBuffer method that returns
an empty buffer with a possibly non-empty capacity for use
with append-like APIs.

The typical usage pattern is something like:
	b := bw.AvailableBuffer()
	b = appendValue(b, v)
	bw.Write(b)

It allows logic combining append-like APIs with bufio.Writer to avoid
needing to allocate and manage buffers themselves and allows the
append-like APIs to directly write into the buffer for a bufio.Writer.

Fixes #47527

Change-Id: I9cd169f3f8e8c7cd40818caf3daf1944c826fc66
Reviewed-on: https://go-review.googlesource.com/c/go/+/345569
Trust: Joe Tsai <[email protected]>
Run-TryBot: Joe Tsai <[email protected]>
TryBot-Result: Go Bot <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>
(cherry picked from golang.org/cl/345569)

e44d304e5486d10f5485250ed5ba58fffd438d29

build-e44d304e5486d10f5485250ed5ba58fffd438d29

Merge remote-tracking branch 'origin/release-branch.go1.17' into tail…

118f76c18c3f755ba0e6211e170a6422871f2791

build-118f76c18c3f755ba0e6211e170a6422871f2791

Merge remote-tracking branch 'origin/release-branch.go1.17' into tail…