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Discard zero address range eh_frame FDEs

Matthias Klose doko@ubuntu.com
Thu Oct 9 07:23:00 GMT 2014 
Am 04.10.2014 um 15:25 schrieb Alan Modra:
> Zero address range FDEs are useless because they can't match any
> address.  In fact, worse than useless because the .eh_frame_hdr lookup
> table matching addresses to FDEs does not contain information about
> the FDE range.  The table is sorted by address;  Range is inferred by
> the address delta from one entry to the next.  So if a zero address
> range FDE is followed by a normal non-zero range FDE for the same
> address, everything is good.  The zero address range FDE will be seen
> as having zero range, and the normal FDE an address range up to the
> next FDE.  However, the qsort could just as easily sort the FDEs in
> the other order, in which case the normal FDE would be seen to have a
> zero range.

this still leaves some link failures for more unusual packages, where ld -r is
used to create intermediate files.
Filed https://sourceware.org/bugzilla/show_bug.cgi?id=17467 and put together a
tarball with the object files for x86_64.

Matthias
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