Re: [TESTING]: one more boot2 shrinking patch

On Thu, Mar 10, 2011 at 09:20:58AM -0500, John Baldwin wrote:
> On Wednesday, March 09, 2011 6:24:36 pm Dimitry Andric wrote:
> > On 2011-03-09 14:23, John Baldwin wrote:
> > >> gcc nor clang emits any code to initialize static type foo = 0;
> > >> because it's expected that BSS is zeroed, which is not the case
> > >> in boot2 so we have to initialize that explicitly
> > > It used to be that if you explicitly initialized a variable to 0, it was
> > > initialized to 0 in .data, but now gcc and clang recognize it is set to 0 and
> > > move it to .bss.  There appears to be no way to turn this feature off,
> > 
> > Yes, there is; both gcc and clang have this option to turn it off:
> > 
> > -fno-zero-initialized-in-bss
> >      If the target supports a BSS section, GCC by default puts variables
> >      that are initialized to zero into BSS. This can save space in the
> >      resulting code.
> > 
> >      This option turns off this behavior because some programs
> >      explicitly rely on variables going to the data section. E.g., so
> >      that the resulting executable can find the beginning of that
> >      section and/or make assumptions based on that.
> > 
> >      The default is -fzero-initialized-in-bss.
> 
> Hah, that is better then.  Thanks! I should have searched about this more
> myself. :(  Roman, can you try reverting the kname changes and adding this
> to CFLAGS instead for both compilers?

when I put -fno-zero-initialized-in-bss clang does not fit by 1.7K and
gcc by 0.5K, we dont want this :)

roman