[U-Boot] [PATCH] examples/standalone: Remove relocation compile flags for PowerPC

[Peter Tyser]

On Fri, 2010-09-10 at 14:53 -0500, Timur Tabi wrote:
> On Fri, Sep 10, 2010 at 2:49 PM, Wolfgang Denk <wd at denx.de> wrote:
> 
> > AFAICT you did not reply to this, and the problem is still unsolved.
> >
> > Do you still have this on your list?
> 
> Sorry, I'm confused.  What exactly do you want me to do?  Since you
> applied Peter's patch, the problem has gone away for me.

Wolfgang applied the "examples/standalone: Remove relocation compile
flags for PowerPC" patch.  That patch should remove the few bytes of
relocation cruft that bumped up the first function address by a few
bytes in standalone images.

However, I think there's still the issue that if there are multiple
functions in a standalone application there's no guarantee the entry
point function will be at the base of the image.  eg if the app were:

int helper_func() {
	code()...
}

int entry_point() {
	// application entry point
}

The entry point wouldn't be at the base of the image, it'd be offset by
the size of helper_func(), and it would jump around depending on
compiler version, flags, etc.

My last question on the issue was:
It looks like the -fno-toplevel-reorder flag is only available in gcc >=
4.2 (http://gcc.gnu.org/gcc-4.2/changes.html released May 2007).  So, do
we add support to U-Boot to conditionally check for the gcc version like
Linux to know when to use -fno-toplevel-reorder?  Or do we use a linker
script that would support more versions of gcc at the cost of more
complexity?

I never heard back about the preferred method.  I'd personally lean
towards checking for compiler version and using the gcc version check +
-fno-toplevel-reorder.

Best,
Peter