[plt-scheme] fix for (sin 12345678901234567890123)

> So, on c.l.s. it has been indirectly pointed out that (sin
> 12345678901234567890123) obeys the following curious invariant in
> MzScheme
> 202 on Windows:
> 
> 	(define oleg-num 12345678901234567890123)
> 	(eqv? (exact->inexact oleg-num) (sin oleg-num)) => #t
> 
> With Microsoft's C compiler, the problem seems to be caused by use of
> the
> /O2 compiler option.  The c.l.s. thread and my latest message there
> gives
> more detail.
> 
> This might be fixable for PLT Scheme's Windows version by checking
> whether
> Visual Studio 6.0 Service Pack 3 fixes it, per
> http://support.microsoft.com/default.aspx?scid=KB;en-us;q217033, which
> seems
> related.  I haven't tested this myself.

MzScheme v202 for Windows was compiled with Visual Studio .NET (VC7), so
I'd guess earlier Service Packs for VC6 won't help.

-- Paul