Re: How to use -dbg packages?
On Thursday 24 August 2006 1:32 pm, Bernd Schubert wrote:
> I need to debug kxkb and its library calls. I just tried to install
> kdebase-dbg and kdelibs-dbg, but there are no usage instructions
> in /usr/share/doc.
I assume these packages provide the missing symbols that are normally stripped
out of distro packages. I don't quite know for sure, because I've never
installed one, but I can intuit what they're for. Namely, to provide
ordinary users the means to avoid submitting useless bug reports full of "(no
debugging symbols found)" messages, without having to go do a full debug
build of the whole affected bit of code. This sounds like an excellent idea
to me!
> There's /usr/lib/debug/usr/bin/kxkb, but doesn't have by default any
> execution bit. Adding, it still fails to run.
You don't run the debugging symbols.
What this is all about is putting a name with a number. The programmer makes
a function called doFoo(), and the compiler translates that into a number
somehow. (I'm not exactly sure how it works.) Say "doFoo()"
becomes "0xb6a897c7"
The numbers are useless to developers, because they have no idea what
function, variable, etc. that number represents. That's what debugging
symbols are for. It's a table to say what name went with what number. These
make executables HUGE, which is why they're stripped out by default. (The
binary for Rosegarden with debugging symbols compiled in is 78 MB!)
So when something crashes, we can figure out that it crashed in doFoo() right
after doFoo() was called by doBar().
> Are those kde -dbg packages only for those kde call traces when an
> application crashes?
Bingo! They're so the result of the little crash dialog will provide
developers with information that they can actually use to gain some real
insight into what caused the crash.
I will remember about the -dbg packages. I have use for those myself, because
Rosegarden sometimes crashes in a KDE or QT call that's a black box to me
because of the problem I'm describing. I have symbols for Rosegarden, but
not KDE.
--
D. Michael 'Silvan' McIntyre ---- Silvan <dmmcintyr@users.sourceforge.net>
Linux fanatic, and certified Geek; registered Linux user #243621
Author of Rosegarden Companion http://rosegarden.sourceforge.net/tutorial/
Reply to: