raul@AMDQC:~$ cd '/usr/lib/freecad-daily/bin/' 
raul@AMDQC:/usr/lib/freecad-daily/bin$  gdb FreeCAD
GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.5) 7.11.1
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Reading symbols from FreeCAD...(no debugging symbols found)...done.
(gdb) handle SIG33 noprint nostop
Signal        Stop	Print	Pass to program	Description
SIG33         No	No	Yes		Real-time event 33
(gdb) run
Starting program: /usr/lib/freecad-daily/bin/FreeCAD 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
FreeCAD 0.17, Libs: 0.17R13331 (Git)
© Juergen Riegel, Werner Mayer, Yorik van Havre 2001-2018
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  ####  # # #  # #  #  #     #####  #   # 
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  #     #   #    #     #    #     # #   #  ##  ##  ##
  #     #   #### ####   ### #     # ####   ##  ##  ##

[New Thread 0x7fffde478700 (LWP 31114)]
[New Thread 0x7fffddc77700 (LWP 31115)]
[New Thread 0x7fffdd1a9700 (LWP 31116)]
[New Thread 0x7fffccea0700 (LWP 31117)]
[New Thread 0x7fffc7fff700 (LWP 31119)]
[New Thread 0x7fffbca45700 (LWP 31120)]
[New Thread 0x7fffbc244700 (LWP 31121)]
[Thread 0x7fffccea0700 (LWP 31117) exited]
[New Thread 0x7fffccea0700 (LWP 31124)]
[New Thread 0x7fff75ca8700 (LWP 31125)]
[New Thread 0x7fff74ced700 (LWP 31126)]
[New Thread 0x7fff6f436700 (LWP 31128)]
[New Thread 0x7fff6ec35700 (LWP 31129)]
[New Thread 0x7fff6e434700 (LWP 31130)]
[New Thread 0x7fff58d7e700 (LWP 31131)]
[New Thread 0x7fff5897d700 (LWP 31132)]
[New Thread 0x7fff5857c700 (LWP 31133)]
[Thread 0x7fffc7fff700 (LWP 31119) exited]
[Thread 0x7fff6f436700 (LWP 31128) exited]
FreeCAD: /build/freecad-daily-HVw0eJ/freecad-daily-0.17~alpha1+git201802241852~ubuntu16.04.1/src/Mod/Spreadsheet/App/PropertySheet.cpp:381: const Spreadsheet::Cell* Spreadsheet::PropertySheet::cellAt(App::CellAddress) const: Assertion `i != data.end()' failed.

Thread 1 "FreeCAD" received signal SIGABRT, Aborted.
0x00007ffff46e7428 in __GI_raise (sig=sig@entry=6)
    at ../sysdeps/unix/sysv/linux/raise.c:54
54	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0  0x00007ffff46e7428 in __GI_raise (sig=sig@entry=6)
    at ../sysdeps/unix/sysv/linux/raise.c:54
#1  0x00007ffff46e902a in __GI_abort () at abort.c:89
#2  0x00007ffff46dfbd7 in __assert_fail_base (fmt=<optimized out>, 
    assertion=assertion@entry=0x7fff6d3dee16 "i != data.end()", 
    file=file@entry=0x7fff6d3df0a0 "/build/freecad-daily-HVw0eJ/freecad-daily-0.17~alpha1+git201802241852~ubuntu16.04.1/src/Mod/Spreadsheet/App/PropertySheet.cpp", line=line@entry=381, 
    function=function@entry=0x7fff6d3df8a0 "const Spreadsheet::Cell* Spreadsheet::PropertySheet::cellAt(App::CellAddress) const") at assert.c:92
#3  0x00007ffff46dfc82 in __GI___assert_fail (
    assertion=0x7fff6d3dee16 "i != data.end()", 
    file=0x7fff6d3df0a0 "/build/freecad-daily-HVw0eJ/freecad-daily-0.17~alpha1+git201802241852~ubuntu16.04.1/src/Mod/Spreadsheet/App/PropertySheet.cpp", 
    line=381, 
    function=0x7fff6d3df8a0 "const Spreadsheet::Cell* Spreadsheet::PropertySheet::cellAt(App::CellAddress) const") at assert.c:101
#4  0x00007fff6d3a8fc0 in Spreadsheet::PropertySheet::cellAt(App::CellAddress) const () from /usr/lib/freecad-daily/lib/Spreadsheet.so
#5  0x00007fff6d3a8ff7 in Spreadsheet::PropertySheet::getSpans(App::CellAddress, int&, int&) const () from /usr/lib/freecad-daily/lib/Spreadsheet.so
#6  0x00007fff6d10eb49 in SpreadsheetGui::SheetTableView::updateCellSpan(App::CellAddress) () from /usr/lib/freecad-daily/lib/SpreadsheetGui.so
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