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For this function it seems like whoever wrote i= t didn't=0A= understand how to accurately evaluate polynomials - the input range of neva= l/deval=0A= is (0.0, 4.0] so the repeated multiplies actually multiply the rounding err= ors...=0A= =0A= > But I guess my point is that SET_RESTORE_ROUND without barriers is a foot= gun. =0A= > I guess I should commit my patch and perhaps see about writing some more = for other=0A= > uses of the macro?=0A= =0A= The patch LGTM. Yes more patches would be welcome. It's a good idea to chec= k=0A= what happens if you remove the SET_RESTORE_ROUND - there will be cases wher= e=0A= the ULP is good enough.=0A= =0A= Cheers,=0A= Wilco=