[PATCH] D24230: [ELF] Linkerscript: Fix handling of empty sections

[Rui Ueyama via llvm-commits]

On Wed, Sep 7, 2016 at 2:22 AM, Eugene Leviant <evgeny.leviant at gmail.com>
wrote:

> evgeny777 added a comment.
>
> > I'm wondering why we need to remove empty output sections from output. I
> cannot think of a reason to not leave them as is except small file/virtual
> address space wastes for the section table slot for the empty section. Do
> we need to handle it as a special case?
>
>
> Besides wasting some (small) space in ELF image I see two potential issues
>
> a) What type and attributes will you assign for those empty sections? If
> you flag them with SHF_ALLOC you may end up having extra LOAD segments in
> ELF image. If you don't, then you'll have to treat them specially in
> assignAddresses.
>

If you do the latter, you'd probably need to add only a few lines to
assignAddresses, which seems a fairly good deal.

b) All "special" sections listed in linker script (like .got, .eh_frame and
> so on) will have duplicates in ELF image, because they don't consist of
> input sections. I don't know if this is a real problem, but looks confusing
> at the very least (IMHO)
>

By duplicates, do you mean we'll end up having two or more special sections
with the same name (e.g. having two .got sections)? If so, I think I don't
understand how this would happen. What am I missing?
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