Backport #3357: r25671
http://redmine.ruby-lang.org/issues/show/3357
e$B5/I<<Te(B: Nobuyoshi N.
e$B%9%F!<%?%9e(B: Assigned, e$BM%@hEYe(B: Normal
e$BC4Ev<Te(B: Yuki S., e$B%+%F%4%je(B: build
r25671e$B$Ne(Bbackporte$B$r$*4j$$$7$^$9!#e(B
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