rev12093: crash on launch with default prefs from stable (0.48.4)

[su_v]

Inkscape 0.48+devel r12093 crashes on launch if the preferences file originates from current stable version (see attached):

Steps to reproduce:
1) mv ~/.config/inkscape{,-bkp}
2) launch and quit inkscape 0.48.4
--> creates 'preferences.xml' with default values (among them 'Sans' as default font)
3) launch current trunk r12093

Expected result:
Inkscape trunk launches, and possibly complains about the missing font 'Sans' when using the text tool (see also bug #1002757)

Actual result:
Inkscape crashes before even opening the main document window:

Program received signal SIGSEGV, Segmentation fault.
sp_font_selector_get_best_style (font=0x3141b40, list=0x0) at ../../src/widgets/font-selector.cpp:456
456 tempFont = (font_factory::Default())->FaceFromUIStrings(family.c_str(), static_cast<char*>(list->data));

Tested systems:
Reproduced with Inkscape 0.48+devel r12093 on:
- Ubuntu 12.04 (64bit, VM), inkscape-trunk from PPA, pango 1.30.0
- Ubuntu 12.10 (64bit, VM), local trunk build, pango 1.30.1
- Mac OS X 10.5.8 (32bit Intel), pango 1.28.8
- Mac OS X 10.74 (64bit), pango 1.30.1, 1.32.5

Not reproduced with r12092 and older revisions.

[su_v (suv-lp)]

Backtrace from Ubuntu 12.10, Inkscape 0.48+devel r12093

[su_v (suv-lp)]

Full backtrace from r12093 debug build with less optimization, on OS X 10.7.4

[jazzynico (jazzynico)]

Confirmed on Debian testing, Inkscape revision 12093.
Same backtrace.

[su_v (suv-lp)]

Alternative steps to reproduce:

1) mv ~/.config/inkscape{,-bkp}
2) launch inkscape trunk (ok)
3) switch to the text tool
(do not click on the canvas yet, we only want to change the default font quickly!)
4) set default font to a non-installed font name:
(overtype default font name "sans-serif" e.g. with "fooooooo", press <Return>)
5) quit inkscape
6) launch inkscape trunk again
--> crash

or:

1) mv ~/.config/inkscape{,-bkp}
2) launch inkscape trunk (ok)
3) switch to the text tool
(do not click on the canvas yet, we only want to change the default font quickly!)
4) set default font to a non-installed font name:
(overtype default font name "sans-serif" e.g. with "fooooooo", press <Return>)
5) now click on the canvas once and create a new text object (with default font "fooooooo")
--> works ok
6) while still in the text tool context, click with the mouse on an empty canvas area to create a second new text object
--> crash

[Johan Engelen (johanengelen)]

prevent crash in r12094.
there is some fallback behavior code for font styles that is incomplete and causes the crash, so keep this bug open. I've added a comment in the code in r12095. I think Tav should take a look.

[Tavmjong Bah (tavmjong-free)]

Fixed in 12097. I am working on some changes that will superceed this fix but have no ETA for those at the moment.

[su_v (suv-lp)]

With the latest changes in revision 12099, line-height defaults to 0% if Inkscape is launched with fresh preferences (e.g. after resetting the prefs system by removing "$XDG_CONFIG_HOME/inkscape/preferences.xml"):

       style="fill:black;fill-opacity:1;stroke:none;font-family:sans-serif;font-style:normal;font-weight:normal;font-size:40px;line-height:0%;letter-spacing:0px;word-spacing:0px"

Not reproduced with r12098 and earlier revisions (default line-height was 125%):

       style="fill:black;fill-opacity:1;stroke:none;font-family:sans-serif;font-style:normal;font-weight:normal;font-size:40px;line-height:125%;letter-spacing:0px;word-spacing:0px"

[Tavmjong Bah (tavmjong-free)]

Fixed, I hope, in 12101. timing of the creation and Initialization of widgets is something of a black art.

[su_v (suv-lp)]

AFAICT this has been fixed, closing.