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- From: Paul Schlie <schlie at comcast dot net>
- To: <gcc at gcc dot gnu dot org>
- Date: Sun, 02 Jan 2005 11:46:43 -0500
- Subject: Re: -funsafe-loop-optimizations
> Kai Henningsen wrote:
>> email@example.com (Zdenek Dvorak) wrote:
>> In particular programs that might get misscompiled with
>> -funsafe-loop-optimizations are usually not portable,
>> since they depend on exact sizes of types.
> Well, not portable everywhere, but often portable to a large number of
> architectures - such as most 32 bit architectures, for example - as those
> typically share those exact sizes.
> Which might easily be enough for a given project. That's a *large* part of
> the market.
> (For example, how many programmers outside the small end of the embedded
> market still care that int might be 16 bit? Assuming at-least-32 is "not
> portable" - but very, very common; in fact, I believe it's been in the GNU
> coding guidelines since long before this was confined to the embedded
Well considering the fact that most of the worlds processor consumption (by
orders of magnitude), are based, and likely will continue to be based 16-bit
or less processor architectures, which not only care about 16-bit or less
ints and pointers, but rely on them; it should likely be considered
sufficiently significant to warrant concern. (although fortunately, most
optimizations related to overcoming inefficiencies of deeply pipelined
larger machines are largely irrelevant on smaller lightly pipelined
architectures with closely coupled memory sub-systems).