W dniu 18.12.2012 13:03, Sven Eden pisze:
> Am Dienstag, 18. Dezember 2012, 12:43:55 schrieb Marcin Mirosław:
>> W dniu 18.12.2012 12:13, Sven Eden pisze:
>
> (snip, because this has nothing to do with the previous discussion.)
>
>>>> On my 32-bit machines I have...
>>>>
>>>> FLAGS="-O2 -march=native -mfpmath=sse -fomit-frame-pointer -pipe
>>>> -fno-unwind-tables -fno-asynchronous-unwind-tables" CXXFLAGS="${CFLAGS}"
>>>>
>>>> See http://comments.gmane.org/gmane.linux.busybox/36695 for why I
>>>>
>>>> include "-fno-unwind-tables -fno-asynchronous-unwind-tables". Would I
>>>> have to rebuild system and world without...
>>>>
>>>> -fomit-frame-pointer -fno-unwind-tables -fno-asynchronous-unwind-tables
>>>>
>>>> ...to have debug data available?
>>>
>>> No, you haven't, if you have compiled everything with "-g" or "-ggdb".
>>>
>>> According to the web page you linked, the DWARF-2 tables are then written
>>> into the .debug files. Without -g/-ggdb, they are stripped and no longer
>>> available for debugging.
>>>
>>> So according to your CFLAGS, you'd have to rebuild everything, yes, but a
>>> simple "-g" would do.
>>>
>>> Oh, and "splitdebug" in "FEATURES" would be a good idea, too! ;)
>>
>> Hi Sven!
>> Meseems you are not right, please look at it:
>> $ readelf -p .GCC.command.line /usr/lib64/debug/usr/bin/sqlite3.debug
>>
>> |grep "unwind\|-g"
>>
>> [ 1e2] -grecord-gcc-switches
>> [ 1f8] -ggdb
>> [ 202] -frecord-gcc-switches
>> $ size /usr/bin/sqlite3
>> text data bss dec hex filename
>> 44545 4124 328 48997 bf65 /usr/bin/sqlite3
>>
>>
>> And with -fno-unwind...
>> $ readelf -p .GCC.command.line /usr/lib64/debug/usr/bin/sqlite3.debug
>>
>> |grep "unwind\|-g"
>>
>> [ 1e2] -grecord-gcc-switches
>> [ 1f8] -ggdb
>> [ 202] -frecord-gcc-switches
>> [ 218] -fno-unwind-tables
>> [ 22b] -fno-asynchronous-unwind-tables
>> $ size /usr/bin/sqlite3
>> text data bss dec hex filename
>> 42713 4124 328 47165 b83d /usr/bin/sqlite3
>>
>> As you can see I have splitdebug turned on.
>> Marcin
>
> Hi Marcin,
Hi Sven!
> I am not right with what? All I did was interpreting a quoted link. And what
> is this supposed to mean? So /usr/bin/sqlite3 looses size. Yes. This goes
> along with the quoted link. But did you compare the current size of
> /usr/lib64/debug/usr/bin/sqlite3.debug before and after?
My fault, I didn't respond below correct paragraph. I was thinking about:
>>> According to the web page you linked, the DWARF-2 tables are then written
>>> into
>>> the .debug files. Without -g/-ggdb, they are stripped and no longer
>>> available
>>> for debugging.
I tried to show that without "-g/-ggdb" gcc generates DWARF-2 tables and
strip doesn't remove it from binaries. I pasted examples with sqlite3
compiles with "-ggdb" but I'm getting the same results without debug
flags. When I add -fno-unwind-tables and -fno-asynchronous-unwind-tables
I'm getting smaller size of "text" (and all binary also).
And I agree with all you write about recompiling system with "-g" and
splitdebug.
Hmm, now I think you was thinking only about adding debug information to
Walters' gentoo and didn't want to talk about growing eh_frame...
> Sorry for any inconvenience, but I assure you, I have absolutly no idea what
> you intent to show.
I hope I throwed some light on my earlier answer.
regards,
Marcin
