Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 06 Jun 2012 19:05:59 +0100
From:      Matthew Seaman <matthew@FreeBSD.org>
To:        freebsd-questions@FreeBSD.org
Subject:   Re: Why Clang
Message-ID:  <4FCF9C07.2000607@FreeBSD.org>
In-Reply-To: <4FCF9333.70201@speakeasy.org>
References:  <4FCF9333.70201@speakeasy.org>

next in thread | previous in thread | raw e-mail | index | archive | help
This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--------------enig91CE1C817C026024A8245F05
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

On 06/06/2012 18:28, Thomas D. Dean wrote:
> Has the discussion on why change to clang been made available?

Yes, endlessly.  Mostly on lists like freebsd-hackers@... and at various
conferences and developer summits.  Check the list archives.

> I would like to know the reasoning.

It's simple.  gcc-4.2, which is what the base system compiler is derived
from is:

    * fairly old

    * doesn't perform as well as more recent compilers

    * doesn't adhere to recently established standards

Clearly an update was necessary.  Unfortunately, later versions of gcc
have switched to GPLv3, which is a viral license and unacceptable to the
FreeBSD project.

Therefore clang was chosen from amongst a number of alternatives as the
best replacement.  That makes it sound as if clang is a second class
option compared to recent gcc, but this is certainly not the case:
results from clang are comparable to the latest gcc versions and the
design of clang is such that further optimizations and improvements can
be readily incorporated.

> Or, is it simply a gratuitous  change?

I can assure you that the changes were not made specifically to annoy
you.  Of course there were very solid technical reasons behind what was
selected.

	Cheers,

	Matthew


--=20
Dr Matthew J Seaman MA, D.Phil.
PGP: http://www.infracaninophile.co.uk/pgpkey




--------------enig91CE1C817C026024A8245F05
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"

-----BEGIN PGP SIGNATURE-----
Version: GnuPG/MacGPG2 v2.0.16 (Darwin)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAk/PnAgACgkQ8Mjk52CukIytXACfU2lcpUTkoFNd/5TP1ycd7FwQ
tfcAoIE3OreQLeNt0l5igkceM4j3MqFh
=djx4
-----END PGP SIGNATURE-----

--------------enig91CE1C817C026024A8245F05--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4FCF9C07.2000607>