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Date: Wed, 02 Sep 2015 22:07:27 +0300
From: "Eli Zaretskii (eliz AT gnu DOT org) [via djgpp AT delorie DOT com]" <djgpp AT delorie DOT com>
Subject: Re: different binary output with 32- and 64-bit hosted compilers
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> Date: Wed, 2 Sep 2015 14:53:59 -0400
> From: DJ Delorie <dj AT delorie DOT com>
> 
> > Could someone who feels more at home with assembly please take a look?
> > DJ?
> 
> The difference is in GAS itself, which chooses a longer form of the JE
> opcode here (and no, I can't think of a good reason why):

Perhaps this should be reported to the Binutils maintainers.

> 32:    21d3:	0f 84 47 00 00 00    	je     2220 <_fire_grenade2+0x270>
> 64:    21d3:	74 4b                	je     2220 <_fire_grenade2+0x270>
> 
> There are no other root differences - every other difference is due to
> addresses being different, and even that is limited as an alignment
> shortly after that resynchromizes everything.

Thanks.

So I guess we can conclude that these differences can be disregarded,
at least with a new enough version of GCC.  The fact there are
differences is, of course, an annoyance, but it looks like we will
have to live with that.