Created attachment 62183 [details]
backtrace with symbols
On pc Debian x86 64, with master updated today (with brand new LO profile), i got a crash when trying to change space lining
Steps to reproduce:
1. Open new document in Writer (no need to type anything)
2. Menu "Format", "paragraph", "Indents & Spacings" tab
3. Change Line spacing value (to "Double" for example)
4. Click Ok
Platform (if different from the browser):
Browser: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.4) Gecko/20100101 Firefox/10.0.4 Iceweasel/10.0.4
no crash for me (or warnings under valgrind) with x86_64 76804ffd5546261ac895ff32ab02e36383304d37
If the crash is 100% reproducible, you can try git-bisect to find the commit which introduces it.
Seeing the result of Caolan, I recompiled from scratched with "git-updated" master sources.
No more crash, just noticed this :
warn:legacy.osl:10153:1:/home/julien/compile-libreoffice/libo/svx/source/dialog/dlgutil.cxx:51: Using fallback for field unit - field unit should be provided in ItemSet
Sorry for the noise :-(