Re: Floating-point constant folding in Emacs byte compiler

[Eli Zaretskii]

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> From: Robert Pluim <address@hidden>
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> Date: Mon, 26 Mar 2018 11:39:25 +0200
> 
> >> I imagine that on a 32-bit version of emacs, (byte-compile (lambda (x)
> >> (* #x10000 #x10000))) similarly produces a constant-zero function,
> >
> > The result depends on whether Emacs was build --with-wide-int.  If it
> > was, the result is #[(x) "\300\207" [4294967296] 1], if it wasn't, I
> > get #[(x) "\300\207" [0] 1].
> 
> Hmm, would it be worthwhile to have Emacs signal overflow in such a
> situation (perhaps controlled by a configuration variable) so we could
> fix such issues?

In which of these two cases do you see overflow?

I also don't think I understand the utility of signaling an overflow
error from the byte compiler that happened because it did constant
folding.  What else except bug reports could this yield?