Bug 240597

Version:           1.7.0 (using KDE 4.4.3) 
OS:                Linux

Steps to reproduce:
0) unpack http://iki.fi/lindi/kst/antenna_debug.tar.bz2 and change paths inside antenna_debug_el_error.kst so that it finds its data files. The file is 26M and its md5sum is 1da227c2979733131d2edf4f4621b4f7
1) start kst
2) open antenna_debug_el_error.kst
3) move mouse over el_goal
4) hold down shift
5) press left arrow three times
6) press up arrow three times
7) press down arrow three times
8) release shift
9) press m
10) zoom rectangle (using right arrow) around x=2000000 so that curve is shown 
11) right click el_goal and choose match axes->el_incr
12) data->data manager and curve el_goal->edit...->
13) enable show points and apply

Expected results:
13) points are shown and kst does not crash

Actual results:
2) el_goal, el_incr etc are correctly shown.
13) kst crashes

More info:
1) gdb shows

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff33704b3 in VectorSelector::update (this=0x90d620) at ./vectorselector.ui.h:56
(gdb) thread apply all bt full

Thread 2 (Thread 0x7fffe7b78710 (LWP 26598)):
#0  pthread_cond_timedwait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S:211
No locals.
#1  0x00007ffff64995a5 in ?? () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#2  0x00007ffff6499660 in QThread::usleep(unsigned long) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#3  0x00007ffff7a0d395 in UpdateThread::run (this=0xe8f110) at updatethread.cpp:141
        gotData = true
        force = true
        updateTime = 200
#4  0x00007ffff6499e5b in QThreadInstance::start(void*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#5  0x00007ffff3b0e8ba in start_thread (arg=<value optimized out>) at pthread_create.c:300
        __res = <value optimized out>
        pd = 0x7fffe7b78710
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140737080952592, -6950877591348121408, 140737488344032, 140737080952592, 140737354125376, 3, 6950825291561889984, 6950851693063499968}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = <value optimized out>
        freesize = <value optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#6  0x00007ffff6cdc03d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
No locals.
#7  0x0000000000000000 in ?? ()
No symbol table info available.

Thread 1 (Thread 0x7ffff7fc5760 (LWP 26597)):
#0  0x00007ffff33704b3 in VectorSelector::update (this=0x90d620) at ./vectorselector.ui.h:56
        i = {node = 0x6345f0}
        prev = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0x90d480, static shared_null = 0x628e20}
        found = false
        vectors = {<QValueList<QString>> = {sh = 0xe896d0}, <No data fields>}
#1  0x00007ffff7a3f502 in KstCurveDialogI::update (this=0x8bd640) at kstcurvedialog_i.cpp:234
No locals.
#2  0x00007ffff7a7f72a in KstApp::updateDialogs (this=0x69d380, onlyVisible=true) at kst.cpp:2173
No locals.
#3  0x00007ffff7a83841 in KstApp::qt_invoke (this=0x69d380, _id=237, _o=0x7fffffffcd20) at kst.moc:634
No locals.
#4  0x00007ffff64fc617 in QObject::activate_signal(QConnectionList*, QUObject*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#5  0x00007ffff64fe85a in QObject::activate_signal(int) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#6  0x00007ffff7a5fbd2 in KstDoc::updateDialogs (this=0x76e0e0) at kstdoc.moc:132
No locals.
#7  0x00007ffff7a5fecf in KstDoc::qt_emit (this=0x76e0e0, _id=3, _o=0x7fffffffce10) at kstdoc.moc:182
No locals.
#8  0x00007ffff64fc64f in QObject::activate_signal(QConnectionList*, QUObject*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#9  0x00007ffff680842d in QSignal::signal(QVariant const&) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#10 0x00007ffff6515f14 in QSignal::activate() () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#11 0x00007ffff651c468 in QSingleShotTimer::event(QEvent*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#12 0x00007ffff649f725 in QApplication::internalNotify(QObject*, QEvent*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#13 0x00007ffff64a04aa in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#14 0x00007ffff5eab4a4 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdecore.so.4
No symbol table info available.
#15 0x00007ffff6496023 in QEventLoop::activateTimers() () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#16 0x00007ffff6450abe in QEventLoop::processEvents(unsigned int) () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#17 0x00007ffff64b5fa1 in QEventLoop::enterLoop() () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#18 0x00007ffff64b5e62 in QEventLoop::exec() () from /usr/lib/libqt-mt.so.3
No symbol table info available.
#19 0x000000000041521b in main (argc=1, argv=0x7fffffffe908) at main.cpp:850
        color = {static color_init = true, static globals_init = true, static colormodel = QColor::d32, d = {argb = 1224736768, d8 = {argb = 1224736768, pix = 84 'T', invalid = 82 'R', dirty = 73 'I', direct = 68 'D'}, d32 = {argb = 1224736768, pix = 1145655892}}}
        pngfile = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0xe986e0, static shared_null = 0x628e20}
        bCaption = false
        hsList = {sh = 0xe995a0}
        nOK = false
        wizardfile = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0xe988d0, static shared_null = 0x628e20}
        psdList = {sh = 0xe99560}
        eq_i = {node = 0x0}
        printfile = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0xe98c70, static shared_null = 0x628e20}
        print_and_exit = false
        bIcon = false
        kst = 0x69d380
        ycolList = {sh = 0x7f9920}
        errorList = {sh = 0xe995e0}
        i_ycol = 32767
        mat_i = {node = 0x0}
        n_y = 0
        bMiniIcon = false
        yEqList = {sh = 0xe98ad0}
        hs_string = {node = 0x0}
        showQuickStart = true
        showDataWizard = false
        in = {skip = 1, doskip = 255, doave = 127, dolegend = false, n = -134406144, f = 32767, rate = 6.9533558073417292e-310, len = 0, has_points = false, sep_plots = false, n_plots = -155237816, n_cols = 32767, n_rows = -136401596, VUnits = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0x628e20, static shared_null = 0x628e20}, RUnits = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0x628e20, static shared_null = 0x628e20}}
        matrixList = {sh = 0xe98b80}
        args = 0x6402f0
        rc = 0
        i_file = 1
        i_curve = 1
        fullPath = {static null = {static null = <same as static member of an already seen type>, d = 0x628e20, static shared_null = 0x628e20}, d = 0x628e20, static shared_null = 0x628e20}
        aboutData = {mAppName = 0x41e0bb "kst", mProgramName = 0x41e0b7 "Kst", mVersion = 0x41e0b1 "1.7.0", mShortDescription = 0x41e750 "Kst: a data viewing program.", mLicenseKey = 1, mCopyrightStatement = 0x41e0e8 "(c) 2000-2007 Barth Netterfield", mOtherText = 0x0, mHomepageAddress = 0x41e0d3 "http://kst.kde.org/", mBugEmailAddress = 0x41e0bf "submit@bugs.kde.org", mAuthorList = {sh = 0x63eed0}, mCreditList = {sh = 0x63ef30}, mLicenseText = 0x0, d = 0x63ef90}
        app = <incomplete type>
        i_v = 65535
        i_plot = -6224

(gdb) x/5i $rip
=> 0x7ffff33704b3 <_ZN14VectorSelector6updateEv+369>:	mov    (%rax),%rdx
   0x7ffff33704b6 <_ZN14VectorSelector6updateEv+372>:	add    $0x10,%rdx
   0x7ffff33704ba <_ZN14VectorSelector6updateEv+376>:	mov    (%rdx),%rdx
   0x7ffff33704bd <_ZN14VectorSelector6updateEv+379>:	mov    %rax,%rdi
   0x7ffff33704c0 <_ZN14VectorSelector6updateEv+382>:	callq  *%rdx
(gdb) info register
rax            0x68	104
rbx            0x69dd00	6937856
rcx            0x0	0
rdx            0x6345f0	6505968
rsi            0x7fffffffcba0	140737488341920
rdi            0x634600	6505984
rbp            0x7fffffffcbe0	0x7fffffffcbe0
rsp            0x7fffffffcb30	0x7fffffffcb30
r8             0x113d0a8	18075816
r9             0x67e5	26597
r10            0x6c006500200073	30399731278545011
r11            0x7ffff6774090	140737328398480
r12            0x7fffffffce28	140737488342568
r13            0x76e0e0	7790816
r14            0x7fffffffcd20	140737488342304
r15            0x1	1
rip            0x7ffff33704b3	0x7ffff33704b3 <VectorSelector::update()+369>
eflags         0x10202	[ IF RF ]
cs             0xe033	57395
ss             0xe02b	57387
ds             0x0	0
es             0x0	0
fs             0x0	0
gs             0x0	0



Reproducible: Sometimes