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Gunderson wrote: >> On Thu, Mar 24, 2022 at 03:52:27PM +1030, Alan Modra wrote: >>> Huh, I remember looking at this code a while ago and finding it >>> confusing. I think the code would be clearer, and behave the same on >>> normal line number info with the following patch: >> >> An interesting question is: Do you want to keep searching through >> compilation units once you've found a match with a line number? >> Should we go straight to =E2=80=9Cgoto done=E2=80=9D then? >=20 > This would be reverting commit 240d6706c6a2. In > https://sourceware.org/bugzilla/show_bug.cgi?id=3D15935#c3 I came to the > conclusion that the pr15935 testcase had bogus debug info and closed > the bug as invalid. The reporter apparently opened another bug, > https://sourceware.org/bugzilla/show_bug.cgi?id=3D15994 a month later > that Nick fixed by making _bfd_dwarf2_find_nearest_line do extra work. > Which of course is unnecessary with good debug info, but in many cases > we try to make binutils give the best result even with bad input. I > don't know the details beyond that. It might have been that the > compiler producing the bad debug info was one supported by RedHat. >=20 > Now we have pr28592 and others complaining that objdump or addr2line > have significantly slowed. Given that pr15935 dates back to 2013, I > would presume that people have moved on from whatever broken compiler > produced bad line info, and that we should indeed revert commit > 240d6706c6a2. Nick? Since I ended up working on that function as well, I did notice another potentially relevant aspect: The adjustment done back at the time was only for the case of already processed CUs. The subsequent loop reading any remaining ones doesn't similarly attempt to find a better match. IOW the effects of that change can only have been partial anyway. Jan