-ffast-math and floating point reordering

[Dale Johannesen]

One point I haven't seen yet:
A couple of strict-constructionists have asserted that people
who want reassociation done in a nonstandard way can easily rewrite 
their
code to achieve this.  This is not really true, because such expressions
often arise as a result of other optimizations, in a way that isn't 
obvious
from the source.  Offhand, inlining, unrolling, and constant/copy 
propagation
can all do it, and there are probably more.