From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.gentoo.org ([140.105.134.102] helo=robin.gentoo.org) by nuthatch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1FnOuW-0007Ef-Pk for garchives@archives.gentoo.org; Mon, 05 Jun 2006 23:55:05 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.6/8.13.6) with SMTP id k55NsIlW028838; Mon, 5 Jun 2006 23:54:18 GMT Received: from mail.tassoneent.com (tassoneent.com [64.34.163.30]) by robin.gentoo.org (8.13.6/8.13.6) with ESMTP id k55NsIpW004599 for ; Mon, 5 Jun 2006 23:54:18 GMT Received: from tassadar (localhost [127.0.0.1]) by mail.tassoneent.com (Postfix) with ESMTP id 4EC34CB293; Mon, 5 Jun 2006 16:54:17 -0700 (PDT) Subject: Re: [gentoo-java] Re: How to predetermine if ebuilds will compile with 1.5? From: Greg Tassone To: gentoo-java@lists.gentoo.org In-Reply-To: <44843F50.4020706@seznam.cz> References: <44833F92.1020201@seznam.cz> <44843F50.4020706@seznam.cz> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-X2++Z+Fma5StmZw1YqVK" Date: Mon, 05 Jun 2006 16:54:28 -0700 Message-Id: <1149551668.8337.32.camel@tassadar> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-java@gentoo.org Mime-Version: 1.0 X-Mailer: Evolution 2.4.2.1 X-Archives-Salt: 246f7516-5701-4100-b915-f623df88e13b X-Archives-Hash: 03c38d3773816f762b1229dd158c7a27 --=-X2++Z+Fma5StmZw1YqVK Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Mon, 2006-06-05 at 16:27 +0200, Caster wrote: > ... > Somebody correct me if I'm wrong, but the bytecode compiled will be the > same no matter which JDK you use. Any optimisations are done with > run-time JIT compiling, and depends on the VM running the bytecode > (which can be different from the VM used to compile). I think this statement is a little too broad to be considered correct. The compiler can (and often does) make changes to the resulting binaries that may be VM-level specific (e.g., targeted for a 1.5 VM). Consider the "-target" argument for javac, for example, which "Allow[s] javac to use 1.5 specific features in the libraries and virtual machine" (http://java.sun.com/j2se/1.5.0/docs/relnotes/features.html ). For more information see the following in the section labeled "Cross-Compilation Options": http://java.sun.com/j2se/1.5.0/docs/tooldocs/solaris/javac.html I also found some interesting information about different bytecode versions here: http://alumnus.caltech.edu/~leif/opensource/bcver/BcVerTask.html More information can be found in Sun articles referenced there. Finally, it looks like some information appears in the following JSR abstract: http://www.jcp.org/en/jsr/detail?id=3D202 ~ Greg --=-X2++Z+Fma5StmZw1YqVK Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (GNU/Linux) iD8DBQBEhMQ0aI3pdOrDO40RAmssAKCgztU8Ed9V+cx48Sf9I8HG4rY4wACdE3XC Kqjn+Ac0eQb6DO7xk2HGl+Q= =wNDn -----END PGP SIGNATURE----- --=-X2++Z+Fma5StmZw1YqVK-- -- gentoo-java@gentoo.org mailing list