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Re: How to handle "-march=native"?
In message <rmippoj4onw.fsf%fnord.ir.bbn.com@localhost>
on Thu, 26 Dec 2013 10:28:35 -0500,
Greg Troxel <gdt%ir.bbn.com@localhost> wrote:
>> # GCC 4.3+ can also produce faster executables when its used.
> Sure, but then they aren't portable.
> It seems there are multiple things going on:
> 1) there may be some bugs about cpu detection, particulaly in various
> vm environments, or about the mapping of flags to instructions.
It mighg be temporary problem since vcvtsi2sdq instruction works after
reboot OS X (and suspend/resume guest OS, NetBSD 6.1_STABLE).
> 2) upstream code is trying to build a binary that is optimized for the
> CPU it is built on, which is basically the wrong thing to do in the
> general case
> You may be running into problem (1), which is just bugs to fix. But
> problem 2 is (from the pkgsrc viewpoint) a bug in the upstream code.
> In my opinion, code should be produced that conforms to the system ABI,
> which means not using cpu-specific instructions.
> I think your option 1 is the right approach.
I'll add a option to CONFIGURE_ARGS. But I still think allow build
with optimized binary could be provided by PKG_OPTIONS.
Takahiro Kambe <taca%back-street.net@localhost>
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