Re: eh_frame_hdr warning

[Jakub Jelinek <jakub at redhat dot com>]

On Mon, Apr 28, 2008 at 02:23:08PM +0930, Alan Modra wrote:
> On Sat, Apr 26, 2008 at 02:33:34PM +0100, Nathan Sidwell wrote:
> > Is there something else I should be overriding?
> 
> Prevent ld adding adding .eh_frame_hdr entirely, perhaps, by clearing
> link_info.eh_frame_hdr.  Is there any point in having it without a
> table?

Yes, even without the table .eh_frame_hdr is needed.  If it is not present,
the PT_GNU_EH_FRAME phdr isn't present and thus libgcc will assume there is
no unwind info at all.

Before .eh_frame_hdr was introduced, gcc needed unwind info registration
functions in crt* files, but GCCs that rely on .eh_frame_hdr don't have those
in the crt* files.

.eh_frame_hdr serves as a way to find the .eh_frame section, and optionally
contains a binary search table to speed up FDE searching.

	Jakub