From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: force dst_default_metrics to const section
Date: Wed, 08 Aug 2012 00:09:59 +0200
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To: David Miller <davem@davemloft.net>
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On Tue, 2012-08-07 at 14:55 -0700, David Miller wrote:
> From: Ben Hutchings <bhutchings@solarflare.com>
> Date: Tue, 7 Aug 2012 21:15:27 +0100
> 
> > Some day the compiler may be smart enough to ignore the different
> > between explicit and implicit zero-initialisation, and put it back in
> > BSS.  Declaring this __cache_aligned_in_smp might be a better option.
> 
> I'm surprised it doesn't already do this.
> 
> It definitely puts scalar explicit zero initializers into the BSS.

Not a const :


# cat try.c
const int scalar_value = 0;
const int scalar_value_bss;
int scalar_value = 0;
int scalar_value_bss;
main(int argc, char *argv[])
{
return 0;
}
# gcc -o try try.c && nm -v try|grep scalar_value
00000000004005cc R cscalar_value
0000000000601028 B scalar_value
000000000060102c B scalar_value_bss
0000000000601030 B cscalar_value_bss


gcc 4.6.3