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Re: bit_size_type - a data type?
On Mon, May 12, 2008 at 3:24 PM, Richard Kenner
<kenner@vlsi1.ultra.nyu.edu> wrote:
> > I gues you'll get funny effects then, as for Nbit sizetype there's
> > usually no valid mode for (N+8)bit bitsizetype. In fact, I believe
> > bitsizetype simply "inherits" the mode from sizetype.
>
> No. We pick the mode that's *at least* 3 bits wider than sizetype, so
> it's usually the next larger integer mode.
Yes, but for example when cross-compiling from a 32bit host to a 64bit target
that would be TImode which most 32bit hosts cannot handle (in which case
we'd ICE if set_sizetype in this case didn't simply chose to make bitsizetype
the same precision as sizetype...)
So in summary, you cannot really rely on bitsizetype capable of doing what
it is supposed to do.
Richard.