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Re: [PATCH] libdw: dwarf_getsrclines mark highest address as end_sequence.

On Mon, 2013-03-25 at 14:27 -0700, Roland McGrath wrote:
> I think this change is fine but we should have dwarflint complain about
> such malformed DWARF and you should immediately report the bugs in any
> compilers known to produce it.

Yes, I am trying to poke the compiler people. Sadly .debug_line seems to
have a somewhat high percentage of weird quirks. The spec says that
addresses in a sequence may only increases, but (also because of missing
end_sequence markers) you will often find a line program jumps around a
lot and you get multiple rows for the same address. The eu-readelf
--debug-dump=decodedline support helps to spot them more easily.

Especially GCC not emitting prologue_end markers is a pain because that
seems to be the cause of lots of "adhoc heuristics" on how to interpret
these quirks.

There are already a couple of issues filed against this for GCC:

I thought there was also a general bug about the missing
DW_LNS_set_prologue_end but I cannot find it now.



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