go/printer: absolute timing fails on slow devices and breaks test

[68CodingMonkeys]

What version of Go are you using (go version)?

$ go version
go version devel go1.17-03761ede02 Thu Jul 1 19:09:57 2021 +0000 linux/arm

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="arm"
GOBIN=""
GOCACHE="/home/ethereum/.cache/go-build"
GOENV="/home/ethereum/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="arm"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/Projekt/ethereum/goroot/bin/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/Projekt/ethereum/goroot/bin"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/Projekt/ethereum/goroot"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/Projekt/ethereum/goroot/pkg/tool/linux_arm"
GOVCS=""
GOVERSION="devel go1.17-03761ede02 Thu Jul 1 19:09:57 2021 +0000"
GCCGO="gccgo"
GOARM="7"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/dev/null"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -marm -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build711812431=/tmp/go-build -gno-record-gcc-switches"
GOROOT/bin/go version: go version devel go1.17-03761ede02 Thu Jul 1 19:09:57 2021 +0000 linux/arm
GOROOT/bin/go tool compile -V: compile version devel go1.17-03761ede02 Thu Jul 1 19:09:57 2021 +0000
uname -sr: Linux 5.10.17-v7l+
Distributor ID:	Raspbian
Description:	Raspbian GNU/Linux 10 (buster)
Release:	10
Codename:	buster
/lib/arm-linux-gnueabihf/libc.so.6: GNU C Library (Debian GLIBC 2.28-10+rpi1) stable release version 2.28.
gdb --version: GNU gdb (Raspbian 8.2.1-2) 8.2.1

What did you do?

compile on raspberry pi:

1. clone rep with git clone https://go.googlesource.com/go goroot
2. cd goroot/src
3. ./all.bash

What did you expect to see?

ALL TESTS PASSED

What did you see instead?

--- FAIL: TestFiles (0.00s)
--- FAIL: TestFiles/empty.input (10.01s)
printer_test.go:185: testdata/empty.input: running too slowly
--- FAIL: TestFiles/go2numbers.input#01 (10.01s)
printer_test.go:185: testdata/go2numbers.input: running too slowly
--- FAIL: TestFiles/go2numbers.input (10.01s)
printer_test.go:185: testdata/go2numbers.input: running too slowly

Workaround:
./src/go/printer/printer_test.go: line 183
case <-time.After(1000 * time.Second): // plenty of a safety margin, even for very slow machines

[gopherbot]

Change https://golang.org/cl/336433 mentions this issue: go/printer: secure margin for testing on slowly device