[gentoo-amd64] Re: Assembler USE flag unmaskings

[Duncan]

Daniel Iliev <[EMAIL PROTECTED]> posted [EMAIL PROTECTED],
excerpted below, on  Wed, 25 Oct 2006 20:04:43 +0300:

> What about enabling those extensions via C[XX]FLAGS? Is this still a bad
> idea?

In most cases, not necessarily bad, but redundant.  A properly set -march=
will take care of the CFLAGS AND allow the best choice in optimizations
for your individual sub-arch.  The exceptions would be the niches where
there's no really correct -march= setting.  The newest CPUs from both AMD
and Intel have that problem ATM.  AMD's newer CPUs (the ones with pni in
the CPU flags, IIRC) may benefit from -msse3 in addition to -march=k8 (or
alias), while Intel's aren't quite right either, but I've not been
following them close enough to know what the best choice is (altho I know
there's some disagreement). 

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman

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