Delivered-To: listarch-cygwin@sourceware.cygnus.com Mailing-List: contact cygwin-help@sourceware.cygnus.com; run by ezmlm Delivered-To: mailing list cygwin@sourceware.cygnus.com Message-ID: <19990208223512.36113@murlibobo.cs.mu.OZ.AU> Date: Mon, 8 Feb 1999 22:35:12 +1100 From: Fergus Henderson To: OSKAR BERRETEAGA Cc: "'cygwin@sourceware.cygnus.com'" Subject: Re: Double alignment trouble References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.88 In-Reply-To: ; from OSKAR BERRETEAGA on Mon, Feb 08, 1999 at 10:21:25AM +0100 On 08-Feb-1999, OSKAR BERRETEAGA wrote: > > I've been trying to change the way gcc aligns double type variables but > with no possitive result. The newsgroup gnu.gcc.help might be a more appropriate forum for this question. > These are the options I've set with gcc: -malign-double (alone or with > one of the following -march='pentium' -m386 -m486) and the full command > line is: gcc -c test.c -malign-double -o test.o `-malign-double' is the default. If you want to disable it, you need to use `-mno-align-double'. However, this will typically have a negative effect on performance, and may cause binary compatibility problems, so I don't recommend using this option. > I've even used the __attribute__((aligned(2))) for both the struct and > the double var but, again, it seems it has no effect on double > alignment. Please RTFM. The documentation of the `aligned' attribute is quite clear: | This attribute specifies a minimum alignment ... ... ^^^^^^^^ | The `aligned' attribute can only increase the alignment; | but you can decrease it by specifying `packed' as well. -- Fergus Henderson | "Binaries may die WWW: | but source code lives forever" PGP: finger fjh@128.250.37.3 | -- leaked Microsoft memo. -- Want to unsubscribe from this list? Send a message to cygwin-unsubscribe@sourceware.cygnus.com