delorie.com/archives/browse.cgi   search  
Mail Archives: djgpp/2015/09/02/11:15:08

X-Authentication-Warning: delorie.com: mail set sender to djgpp-bounces using -f
From: Martin Str|mberg <ams AT ludd DOT luth DOT se>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: different binary output with 32- and 64-bit hosted compilers
Date: Wed, 2 Sep 2015 14:52:13 +0000 (UTC)
Organization: Aioe.org NNTP Server
Lines: 37
Message-ID: <ms72er$feb$1@speranza.aioe.org>
References: <CAA2C=vBjWACN4ZNsYTeCWXOr9vU9s2s23ZaXvLuCgE=OEWK1Vg AT mail DOT gmail DOT com> <83d1y2cf7e DOT fsf AT gnu DOT org> <CAA2C=vCu9fjcEDr_3_FLMXoRzuvmXw57zRkwchbYRD1SpqS4NA AT mail DOT gmail DOT com> <ms63dr$3k4$1 AT speranza DOT aioe DOT org> <CAA2C=vABL08je+e-uOpgkSAR+_Zrs80AkAzQEbXUc6CJhOq4AA AT mail DOT gmail DOT com>
NNTP-Posting-Host: WLZdEp4S2PR09rkVF8ILdg.user.speranza.aioe.org
X-Complaints-To: abuse AT aioe DOT org
User-Agent: tin/2.2.1-20140504 ("Tober an Righ") (UNIX) (Linux/3.2.0-4-amd64 (x86_64))
X-Notice: Filtered by postfilter v. 0.8.2
Bytes: 2147
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

"Ozkan Sezer (sezeroz AT gmail DOT com) [via djgpp AT delorie DOT com]" <djgpp AT delorie DOT com> wrote:
> I have a source that gives the following asm output difference

> --- g_weapon.s
> +++ ../../g_weapon.s
> @@ -4526,7 +4526,7 @@
>         .long   1065353216
>         .p2align 3
>  LC5:
> -       .long   -1717986918
> +       .long   2576980378
>         .long   1069128089
>         .p2align 2
>  LC13:

Yes, I understand that.

> .. and results in different *.o.  This is with gcc5 (which I really
> don't want to use).

The diff above can't give different bit patterns on 32-bit
two-complements machine. The bits will be
10011001100110011001100110011010 for both -1717986918 and 2576980378.
The differences in .o must be because of something else.

> The original mail shows that with gcc-3.4.6 there are not only differences
> like -858993459 and 3435973837 but also asm output differences.

I have, so far, only seen posts from you with this (IMO) same bits
non-difference.

If there are different opcodes used, it's (much) harder to definitely
say if they mean the same thing. Likely they don't.


-- 
MartinS

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019