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Re: Move unwind info to read-only section on AIX

Hi David,

On Thu, Jul 31, 2014 at 2:22 PM, David Edelsohn <> wrote:
> As the comment in the code states DWARF2 unwind info was placed in the
> data section to prevent the AIX linker from garbage collecting it.
> How are you avoiding that problem?

That comment is very old.  I'm not sure what the original problem was.
The code generated by collect2 which calls register_frame_info_table
has explicit references to the DWARF unwind info.  The linker won't
garbage collect the unwind info as the linker will see it as used
through these references.

> Also, the AIX linker uses "$" for the current location, so the kludge
> of creating PCREL symbols should not be necessary.

I will swap it over to this.

> Using __dso_handle as the base address is underwhelming.

Does the using the TOC sound like a reasonable solution?
Or do you know how to get a reference to the start of the data section
from the AIX assembler/linker?
The ld manpage lists _data, but this symbol doesn't work for shared libraries.


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