UFO crash

[davelab6]

@vernnobile says in https://gist.github.com/davelab6/6362877 that,

The UFO files created now seem to have a major issue. Re-opening them in fontforge on gnu+linux causes fontforge to crash. However this seems to be a fault now with all UFOs now being created by fontforge.

Program received signal SIGSEGV, Segmentation fault.
XMLEntryToPython (doc=0x889dd0, entry=0x0) at ufo.c:972
972     if ( xmlStrcmp(entry->name,(const xmlChar *) "true")==0 ) {
(gdb) bt
#0  XMLEntryToPython (doc=0x889dd0, entry=0x0) at ufo.c:972
#1  0x00007ffff3e8c4d8 in LibToPython (doc=doc@entry=0x889dd0, 
    dict=<error reading variable: Unhandled dwarf expression opcode 0xfa>) at ufo.c:956
#2  0x00007ffff3e8e213 in _UFOLoadGlyph (doc=0x889dd0, 
    glifname=glifname@entry=0x844c40 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/glyphs/_notdef.glif") at ufo.c:1365
#3  0x00007ffff3e90235 in UFOLoadGlyph (
    glifname=0x844c40 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/glyphs/_notdef.glif")
    at ufo.c:1383
#4  UFOLoadGlyphs (
    glyphdir=0x809cf0 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/glyphs", sf=0x88d790)
    at ufo.c:1451
#5  SFReadUFO (
    basedir=basedir@entry=0x888c00 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/", 
    flags=flags@entry=0) at ufo.c:1953
#6  0x00007ffff3ddb96f in _ReadSplineFont (file=0x8683c0, file@entry=0x0, 
    filename=filename@entry=0x888c00 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/", 
    openflags=openflags@entry=0) at splinefont.c:1045
#7  0x00007ffff3ddc54c in ReadSplineFont (
    filename=filename@entry=0x888c00 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/", 
    openflags=openflags@entry=0) at splinefont.c:1248
#8  0x00007ffff3ddc650 in LoadSplineFont (
    filename=0x888c00 "/home/vern/gitHub/topmarks/Regular/src/Kodato-Regular.ufo/", 
    openflags=openflags@entry=0) at splinefont.c:1321
#9  0x00007ffff3c9f88c in ViewPostScriptFont (filename=<optimized out>, openflags=0)
    at fontviewbase.c:1319
#10 0x00007ffff42e5768 in MenuOpen (gw=gw@entry=0x0, UNUSED_mi=UNUSED_mi@entry=0x0, 
    UNUSED_e=UNUSED_e@entry=0x0) at fontview.c:1024
#11 0x00007ffff437d18c in fontforge_main (argc=1, argv=<optimized out>) at startui.c:1258
#12 0x00007ffff1e85ead in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
#13 0x0000000000400961 in _start ()

[vernnobile]

i can confirm that the issue seems to be gnuLinux only. Not able to reproduce on OSX build latest (30_0421). Will test some more on other linux distros.

[vernnobile]

I have reproduced this crash on a fresh install of Debian 7. Fontforge build from git commit e2d6035

Generate UFO file, then open that UFO file. It does seem that not all UFOs cause a crash, but UFO created by older builds of Fontforge are not causing crashes.

These UFOs will also not open in Robofont on OSX (see screenshot of Robofont error below)

backtrace;

Program received signal SIGSEGV, Segmentation fault.
XMLEntryToPython (doc=0x97f6b0, entry=0x0) at ufo.c:972
972     if ( xmlStrcmp(entry->name,(const xmlChar *) "true")==0 ) {
(gdb) bt
#0  XMLEntryToPython (doc=0x97f6b0, entry=0x0) at ufo.c:972
#1  0x00007ffff3e8d4d8 in LibToPython (doc=doc@entry=0x97f6b0, 
    dict=<error reading variable: Unhandled dwarf expression opcode 0xfa>) at ufo.c:956
#2  0x00007ffff3e8f213 in _UFOLoadGlyph (doc=0x97f6b0, 
    glifname=glifname@entry=0x9658f0 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/glyphs/e.glif")
    at ufo.c:1365
#3  0x00007ffff3e91235 in UFOLoadGlyph (
    glifname=0x9658f0 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/glyphs/e.glif") at ufo.c:1383
#4  UFOLoadGlyphs (glyphdir=0x840480 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/glyphs", 
    sf=0x8b3240) at ufo.c:1451
#5  SFReadUFO (basedir=basedir@entry=0x891870 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/", 
    flags=flags@entry=0) at ufo.c:1953
#6  0x00007ffff3ddc96f in _ReadSplineFont (file=0x8a8e40, file@entry=0x0, 
    filename=filename@entry=0x891870 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/", 
    openflags=openflags@entry=0) at splinefont.c:1045
#7  0x00007ffff3ddd54c in ReadSplineFont (
    filename=filename@entry=0x891870 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/", 
    openflags=openflags@entry=0) at splinefont.c:1248
#8  0x00007ffff3ddd650 in LoadSplineFont (
    filename=0x891870 "/home/vern/gitHub/topmarks/Bold/src/Topmarks-Bold-2.ufo/", openflags=openflags@entry=0)
---Type <return> to continue, or q <return> to quit---
    at splinefont.c:1321
#9  0x00007ffff3ca088c in ViewPostScriptFont (filename=<optimized out>, openflags=0) at fontviewbase.c:1319
#10 0x00007ffff42e6768 in MenuOpen (gw=gw@entry=0x0, UNUSED_mi=UNUSED_mi@entry=0x0, 
    UNUSED_e=UNUSED_e@entry=0x0) at fontview.c:1024
#11 0x00007ffff437e18c in fontforge_main (argc=1, argv=<optimized out>) at startui.c:1258
#12 0x00007ffff1e86ead in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
#13 0x0000000000400961 in _start ()```

[frank-trampe]

Saving as sfd, then saving as ufo, and then re-opening works for me at c9c03b4 on Linux Mint 13 on amd64 (using Rokkit from another bug report). Can somebody post a sample corrupt file?

[davelab6]

@vernnobile please post a sample file on gist for @frank-trampe

[vernnobile]

Hmm. I have a ufo file that was first created by Robofont, then openend in Fontforge, then saved as a UFO from fontforge. It can be openend OK in FontForge but will not open in Robofont (see screenshot)
Posted the sfd on gist --> https://gist.github.com/vernnobile/7709172

Also, although FontForge does open the UFO it gives the following warnings;

[frank-trampe]

We've made some stability and some interchange enhancements. Can @vernnobile try this on current master?

[vernnobile]

Frank!
OK, so i tested the corrupt sfd i posted at https://gist.github.com/vernnobile/7709172
The file opens fine, and not even any warnings. Good work & thanks :)