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Mail Archives: cygwin/2007/10/28/04:36:02

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From: Victor Paesa <wzrlpy AT arsystel DOT com>
Subject: Re: llrint implementation in Cygwin
Date: Sun, 28 Oct 2007 09:35:23 +0000 (UTC)
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Hi,

Brian Dessent writes:

> Victor Paesa wrote:
> 
> > I downloaded the gcc-3.4.4 Cygwin source package, and I found that 
> > (apparently) gcc 3.4.4 already had llrint built-in:

[skipped nice detailed explanation on how builtins work]

Thanks!

[...]

> So even if it did have a __builtin_llrint, you would
> not be able to use it any non-trivial manner.
> 
> [ Also note that you did not invoke gcc with optimization above, which
> I'm pretty sure means it won't even consider using optimized builtins. ]

I tried with gcc 4.4.2. If I understood correctly the Changelog, this one
implements llrint(). It compiled out of the box, but indeed I wasn't able 
to use the __builtin_llrint (tried -O2, -O3, -ffast-math, -finline-functions
to no avail).

> > Could that be fixed by adding/removing flags to the configure line used
> > to build gcc 3.4.4 in Cygwin?
> 
> No what needs to be done is add llrint to newlib.  A builtin is not a
> suitable replacement.

Since the builtin way is a dead end, I wonder how is the future Cygwin gcc 
suposed to bring llrint(). Will it use the <mathinline.h> approach or will
it patch newlib?
(since the thread is a bit overheated: please understand it as a technical
question, no trolling intended).

Thanks in advance for your answer,
Victor

P.S. Sorry if Gmane is breaking the thread, I tried cygwin-get DOT 556 AT cygwin DOT com
but it didn't worked.


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