threadDelay behavior 64-bit mac os x

threadDelay 1000000

works as expected in 7.0.1-x86_64
return immediately in DEVELOPMENT 7.1.20110131
hangs eating CPU in STABLE 7.0.1.20110201, 7.0.1.20110211

to reproduce: fire up ghci

import Control.Concurrent
threadDelay 1000000

Edited Mar 09, 2019 by Ian Lynagh -

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