Update #4069: this CL fixes the issue on windows/386.
Signed-off-by: Shenghou Ma <minux@golang.org>
Change-Id: I2d2ea233f976aab3f356f9b508cdd246d5013e2e
Reviewed-on: https://go-review.googlesource.com/7283Reviewed-by: Ian Lance Taylor <iant@golang.org>