Hello. I always get plasma crash with next error:

Application: Рабочее пространство Plasma (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 6695)]

Thread 2 (Thread 0xa8c05b70 (LWP 6697)):
#0 0xffffe424 in __kernel_vsyscall ()
#1 0xb7e2fcb5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2 0xb7eb5cd1 in QWaitCondition::wait () from /usr/lib/qt4/libQtCore.so.4
#3 0xb6c79ff4 in ?? () from /usr/lib/gcc/i686-pc-linux-gnu/4.4.1/libstdc++.so.6
#4 0x088534e8 in ?? ()
#5 0xa8c05288 in ?? ()
#6 0x0846b1c8 in ?? ()
#7 0x00048058 in ?? ()
#8 0xa8c05288 in ?? ()
#9 0xa8c05280 in ?? ()
#10 0x00418937 in ?? ()
#11 0x088534e8 in ?? ()
#12 0xb7942ff4 in ?? () from /usr/lib/qt4/libQtNetwork.so.4
#13 0x0848bea4 in ?? ()
#14 0xb78d8ade in QHostInfo::~QHostInfo () from /usr/lib/qt4/libQtNetwork.so.4
#15 0x00000000 in ?? ()

Thread 1 (Thread 0xb6597b30 (LWP 6695)):
#0 0xffffe424 in __kernel_vsyscall ()
#1 0xb6aaaa36 in nanosleep () from /lib/libc.so.6
#2 0xb6aaa849 in sleep () from /lib/libc.so.6
#3 0xb76fab0f in ?? () from /usr/lib/libkdeui.so.5
#4 0x00000001 in ?? ()
#5 0x00000000 in ?? ()


--------
Please, help me.

https://bugs.kde.org/show_bug.cgi?id=207415

As requested on the bug report, please enable debugging symbols for KDELibs and Plasma ( in KDEBase-Workspace ) and create a new backtrace if you can reproduce.

I have been enabled debug mode. Below full trace:
---------------------------------
Application: Рабочее пространство Plasma (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 6627)]

Thread 2 (Thread 0xa89e1b70 (LWP 6630)):
#0 0xffffe424 in __kernel_vsyscall ()
#1 0xb7de9cb5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2 0xb7e7207c in QWaitCondition::wait () from /usr/lib/qt4/libQtCore.so.4
#3 0xb782f10e in ?? () from /usr/lib/qt4/libQtNetwork.so.4
#4 0xb7e71412 in ?? () from /usr/lib/qt4/libQtCore.so.4
#5 0xb7de56af in start_thread () from /lib/libpthread.so.0
#6 0xb69c43de in clone () from /lib/libc.so.6

Thread 1 (Thread 0xb6473b30 (LWP 6627)):
[KCrash Handler]
#6 0xa8dd8f3a in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#7 0xa8dd8139 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#8 0xa8dd17db in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#9 0xa8dd1c39 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#10 0xa8dd1d19 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#11 0xa8dd2588 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#12 0xa8dd27d8 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#13 0xa8dddab1 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#14 0xa8dde7d6 in ?? () from /usr/lib/kde4/plasma_applet_tasks.so
#15 0xb7f6cb0c in QMetaObject::activate () from /usr/lib/qt4/libQtCore.so.4
#16 0xb7f6e6b0 in QMetaObject::activate () from /usr/lib/qt4/libQtCore.so.4
#17 0xa8e1a04c in TaskManager::TaskGroup::itemAdded () from
/usr/lib/libtaskmanager.so.4
#18 0xa8e28b54 in typeinfo for TaskManager::DesktopsMenu () from
/usr/lib/libtaskmanager.so.4
#19 0x00000000 in ?? ()
---------------------------

Just adding the debug flag is not all you need to do, unfortunately.

Here's the Gentoo guide:
http://www.gentoo.org/proj/en/qa/backtraces.xml

What you need to do is to add "-ggdb" to your C/CXXFLAGS, and "splitdebug" to your FEATURES in the make.conf.

This builds your programs with full debug information, but strips all of it and puts it into the /usr/lib/debug folder, so aside from taking up some extra space on your hard drive, it will not cause any negative performance.

Once you do that, I would probably emerge:
kde-base/kdelibs
kde-base/plasma-workspace
kde-base/plasma-runtime
kde-base/libkworkspace
kde-base/libtaskmanager

Be aware though, that if you leave -ggdb and splitdebug on, it will take lots of space. So if you're short on hard drive space, you should only turn them on them when you're emerging KDE-related packages.

plasma-addons may also be needed.

I get nostrip trace:
--------------------
Application: Рабочее пространство Plasma (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 6666)]

Thread 2 (Thread 0xa88e8b70 (LWP 6669)):
#0 0xffffe424 in __kernel_vsyscall ()
#1 0xb7cfdcb5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2 0xb7d8607c in QWaitCondition::wait (this=0x84a4538, mutex=0x84a4534,
time=4294967295) at thread/qwaitcondition_unix.cpp:87
#3 0xb774310e in QHostInfoAgent::run (this=0x84a4528) at
kernel/qhostinfo.cpp:260
#4 0xb7d85412 in QThreadPrivate::start (arg=0x84a4528) at
thread/qthread_unix.cpp:188
#5 0xb7cf96af in start_thread () from /lib/libpthread.so.0
#6 0xb68d83de in clone () from /lib/libc.so.6

Thread 1 (Thread 0xb6387b30 (LWP 6666)):
[KCrash Handler]
#6 0xa8cecf3a in Tasks::itemTopMargin (this=0x74002f) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/tasks.h:92
#7 0xa8cec139 in AbstractTaskItem::basicPreferredSize (this=0x8a07110) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/abstracttaskitem.cpp:99
#8 0xa8ce57db in TaskItemLayout::preferredColumns (this=0x8114bb0) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskitemlayout.cpp:206
#9 0xa8ce5c39 in TaskItemLayout::gridLayoutSize (this=0x8114bb0) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskitemlayout.cpp:222
#10 0xa8ce5d19 in TaskItemLayout::layoutItems (this=0x8114bb0) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskitemlayout.cpp:245
#11 0xa8ce649c in TaskItemLayout::remove (this=0x8114bb0, item=0x89ed4f8) at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskitemlayout.cpp:136
#12 0xa8ce6624 in TaskItemLayout::removeTaskItem (this=0x8114bb0,
item=0x89ed4f8)
at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskitemlayout.cpp:93
#13 0xa8cf0803 in TaskGroupItem::itemRemoved (this=0x84a9150,
groupableItem=0x8a11c88)
at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1/plasma/applets/tasks/taskgroupitem.cpp:521
#14 0xa8cf27f4 in TaskGroupItem::qt_metacall (this=0x84a9150,
_c=QMetaObject::InvokeMetaMethod, _id=30, _a=0xbffa4988)
at
/var/tmp/portage/kde-base/plasma-workspace-4.3.1/work/plasma-workspace-4.3.1_build/plasma/applets/tasks/taskgroupitem.moc:114
#15 0xb7e80b0c in QMetaObject::activate (sender=0x83ff190,
from_signal_index=<value optimized out>, to_signal_index=22, argv=0xbffa4988)
at kernel/qobject.cpp:3101
#16 0xb7e826b0 in QMetaObject::activate (sender=0x83ff190, m=0xa8d3cb54,
local_signal_index=1, argv=0xbffa4988) at kernel/qobject.cpp:3178
#17 0xa8d2e000 in TaskManager::TaskGroup::itemRemoved () from
/usr/lib/libtaskmanager.so.4
#18 0xa8d3cb54 in typeinfo for TaskManager::DesktopsMenu () from
/usr/lib/libtaskmanager.so.4
#19 0x00000001 in ?? ()
#20 0xbffa4988 in ?? ()
#21 0x08494790 in ?? ()
#22 0x00000000 in ?? ()

The crash is reported at https://bugs.kde.org/show_bug.cgi?id=199325 , and it seems to be fixed on 4.4 (we didn't get reports from it on trunk); I don't know about branch (future 4.3.2)
Regards