[Kdenlive-devel] Segfault after 30 MyThread::run

[Mario Theodoridis]

Hi,
i'm new to this list. I'm also new to video editing, or developing the editor 
for that matter. I'm trying to put together a video using a lot of stills and 
video clips. I started by assembling all the clips i wanted to use. There are 
around 270 of them. Then i started to assemble some footage.
Somewhere along the lines kdenlive started segfaulting.

So i got the source for mlt (git)  and kdenlive (svn), removed the packages, 
built debug versions and ran kdenlive under kdevelop.

I turned on logging for kdenlive and find that after 30 runs of MyThread::run 
things segfault in mlt_properties_find
	property_list *list = this->local;
because 'this' is null. The stack looks like this:

#0 mlt_properties_find() at 
/data/netlocal/foss/video/mlt/src/framework/mlt_properties.c:347
#1 mlt_properties_get_int() at 
/data/netlocal/foss/video/mlt/src/framework/mlt_properties.c:719
#2 producer_set_up_video() at 
/data/netlocal/foss/video/mlt/src/modules/avformat/producer_avformat.c:1604
#3 producer_get_frame() at 
/data/netlocal/foss/video/mlt/src/modules/avformat/producer_avformat.c:2221
#4 producer_get_frame() at 
/data/netlocal/foss/video/mlt/src/framework/mlt_producer.c:577
#5 mlt_service_get_frame() at 
/data/netlocal/foss/video/mlt/src/framework/mlt_service.c:480
#6 Mlt::Service::get_frame(int)() at /home/mario/usr/lib/libmlt++.so.3:-1
#7 MyThread::run() at /data/netlocal/foss/video/kdenlive/src/kthumb.cpp:89
#8 QThreadPrivate::start() at thread/qthread_unix.cpp:265
#9 start_thread() at pthread_create.c:303
#10 clone() at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
#11 ??() at :-1


It's not clear to me which list is the right one for this, as it crashes in 
mlt, but always does after 30 mythread runs.

I've been staring at this code for a day trying to fix it, but am currently 
still rather clueless as to how a lot of it functions. I was hoping to get 
some insight on why this might be happening, so that i or someone else can fix 
it. Unless i'm doing something wrong, in which case i would appreciate some 
cluesticks in that regard.

This all is happening on Kubuntu Maverik 64bit.

Please let me know if this is the wrong list, or more info is needed.

Thanks in advance

Mario