fix for KConfigPrivate::groupList (kconfig.cpp)

[Friedrich W. H. Kossebau]

Am Freitag, 29. Dezember 2023, 16:36:41 CET schrieb Tommaso Massimi:
> On Fri, Dec 29, 2023 at 3:35 PM Friedrich W. H. Kossebau
> <kossebau at kde.org> wrote:
[snip}
> > After a more close look I would partially disagree and point to another
> 
> > possible cause:
> correct, my analisys was wrong, I apologize

All fine, things are so complicated we all get some things wrong in the first 
round of working theory, actually my long reply was also edited & corrected 3 
times (and perhaps still got some thing wrong) :)

> > Now, the backtrace you shared shows that there are more threads active at
> > the same time.
> 
> I'm not sure:
> 
> valgrind can shown more backtraces, in this case:
> 
> the backtrace where the error was detected (read unallocated memory)
> 
> > > ==70026== Invalid read of size 16
> > > ==70026==    at 0x668FAF7: ???
> 
> the backtrace where that memory was allocated
> 
> > > ==70026==  Address 0xcd3c40a is 26 bytes inside a block of size 38
> > > alloc'd
> > > ==70026==    at 0x4848899: malloc (in
> 
> 70026 is the PID, reported on each line. so I see only one thread.

Ah, I might have misread the log as being a execution stack backtrace. So my 
conclusion of this being a threading issue might also be wrong?`

I guess you best upload the full log of valgrind (including how to reproduce 
what you see, i.e. which tool you used with which flag) to a bug report on 
bugs.kde.org.

Cheers
Friedrich