This triggers about 50k times during 32 bit make.bash.

Change-Id: Ia0c2b1a8246b92173b4b0d94a4037626f76b6e73
Reviewed-on: https://go-review.googlesource.com/37998
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>