1. What version of Go are you using (go version)?
   go version devel +f3d5478 Fri Jun 17 19:15:29 2016 +0000 windows/386

2. What operating system and processor architecture are you using (go env)?
   set GOARCH=386
   set GOBIN=C:\Go\bin
   set GOEXE=.exe
   set GOHOSTARCH=386
   set GOHOSTOS=windows
   set GOOS=windows
   set GOPATH=c:\gopath
   set GORACE=
   set GOROOT=C:\Go
   set GOTOOLDIR=C:\Go\pkg\tool\windows_386
   set CC=gcc
   set GOGCCFLAGS=-m32 -fmessage-length=0
   set CXX=g++
   set CGO_ENABLED=0

3. What did you do?

   git clone https://github.com/golang/go.git
   cd go\src
   all

4. What did you expect to see?
   A clean build & test.

5. What did you see instead?
   ...
   ok cmd/compile/internal/test 0.360s
   ok cmd/cover 14.877s
   ok cmd/doc 0.614s
   ok cmd/fix 0.372s
   panic: test timed out after 6m0s

I tried twice:
firsttry.txt
secondtry.txt

The computer is an old and slow netbook:

Please note I have set CGO_ENABLED to zero, to avoid C compiler installation issues.