D-Programming-Language/dmd — pull request #760 by yebblies (2012-02-23 14:40:00+00:00)
Title: Issue 4155 - return of NaN to temporary fails equality test

When evaluating `cast(bool)v` where `v` is a `float` or `double`, and `v` is the result of a function call in `ST(0)` check for nan condition (ZF) to avoid returning the wrong value.

Not tested on x64, it might need to include mmx registers, I'm not really sure how that works.

http://d.puremagic.com/issues/show_bug.cgi?id=4155