x/exp/slog: tests consistently failing on many builders

[bcmills]

greplogs -l -e FAIL\\s+golang\\.org/x/exp/slog --since=2022-08-01 --details

2022-09-09T13:00:31-4397029-218294f/darwin-amd64-10_14
2022-09-09T13:00:31-4397029-218294f/darwin-amd64-10_15
2022-09-09T13:00:31-4397029-218294f/linux-amd64
2022-09-09T13:00:31-4397029-218294f/linux-amd64-longtest
2022-09-09T13:00:31-4397029-218294f/linux-amd64-nocgo
2022-09-09T13:00:31-4397029-218294f/linux-amd64-race
2022-09-09T13:00:31-4397029-218294f/windows-386-2008
2022-09-09T13:00:31-4397029-218294f/windows-386-2008-newcc
2022-09-09T13:00:31-4397029-218294f/windows-amd64-2016
2022-09-09T13:00:31-4397029-218294f/windows-amd64-2016-newcc
2022-09-09T13:00:31-4397029-218294f/windows-amd64-longtest
2022-09-09T13:00:31-4397029-218294f/windows-amd64-longtest-newcc
2022-09-09T13:00:09-91042ec-4108970/darwin-amd64-10_14
2022-09-09T13:00:09-91042ec-4108970/darwin-amd64-10_15
2022-09-09T13:00:09-91042ec-4108970/linux-amd64
2022-09-09T13:00:09-91042ec-4108970/linux-amd64-longtest
2022-09-09T13:00:09-91042ec-4108970/linux-amd64-nocgo
2022-09-09T13:00:09-91042ec-4108970/linux-amd64-race
2022-09-09T13:00:09-91042ec-4108970/windows-386-2008
2022-09-09T13:00:09-91042ec-4108970/windows-386-2008-newcc
2022-09-09T13:00:09-91042ec-4108970/windows-amd64-2016
2022-09-09T13:00:09-91042ec-4108970/windows-amd64-2016-newcc
2022-09-09T13:00:09-91042ec-4108970/windows-amd64-longtest
2022-09-09T13:00:09-91042ec-4108970/windows-amd64-longtest-newcc
2022-09-09T12:46:45-60527bc-4108970/darwin-amd64-10_14
2022-09-09T12:46:45-60527bc-4108970/darwin-amd64-10_15
2022-09-09T12:46:45-60527bc-4108970/windows-386-2008
2022-09-09T12:46:45-60527bc-4108970/windows-386-2008-newcc
2022-09-09T12:46:45-60527bc-4108970/windows-amd64-2016
2022-09-09T12:46:45-60527bc-4108970/windows-amd64-2016-newcc
2022-09-09T12:46:45-60527bc-4108970/windows-amd64-longtest
2022-09-09T12:46:45-60527bc-4108970/windows-amd64-longtest-newcc
2022-09-09T12:41:27-bee5968-4108970/linux-amd64-race
2022-09-09T01:04:57-145caa8-76c94eb/linux-amd64-race
2022-09-06T22:23:43-fcb1a31-c83e1b6/linux-amd64-race

(35 matching logs)

(attn @jba; CC @mknyszek)

[gopherbot]

Change https://go.dev/cl/430075 mentions this issue: slog: fix race failures

[bcmills]

Reopening for one last failure mode on linux-amd64-race:

--- FAIL: TestAlloc (0.00s)
    buffer_test.go:29: got 1 allocs, want 0
FAIL
FAIL	golang.org/x/exp/slog/internal/buffer	0.027s

[gopherbot]

Change https://go.dev/cl/431056 mentions this issue: slog/internal/buffer: don't run alloc test with race detector