dosbox crashed with SIGSEGV

StacktraceTop:
 XGA_GetPoint (x=<value optimized out>,
 XGA_DrawLineBresenham (val=<value optimized out>)
 PageHandler::writew_checked (this=0x80000ee3,
 ?? ()
 ?? ()

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue you are reporting is an upstream one and it would be nice if somebody having it could send the bug to the developers of the software at their bugtracker (http://sourceforge.net/tracker/?group_id=52551&atid=467232) by following the instructions at http://vogons.zetafleet.com/viewtopic.php?t=2949. If you have done so, please tell us the number of the upstream bug (or the link), so we can add a bugwatch that will inform us about its status. Thanks in advance.

I've dug a bit into the issue, and put together a patch for the upstream:

    https://sourceforge.net/tracker/?func=detail&aid=3154782&group_id=52551&atid=467234

@Daniel: that link gives me back an "Error 403: access required" message. Is it a private report?

No, I get the same error too. Looks like SourceForge lossage---I've seen the same issue with some other projects recently.

(Now I wish I'd also posted the patch here...)

FWIW, it seems like SourceForge updated their bug/patch tracker functionality, and forgot to support old URLs.

The current patch tracker for DOSBox is here:

    https://sourceforge.net/p/dosbox/patches/

I don't see my patch in there, however, even though there are a few from about the same time. No idea what happened.

It seems like DOSBox has issues on 64-bit systems. I compiled it from svn and got several warnings related to data type size assumptions. When I run DOSBox in Windows or Wine, there is no problem.

$ file /home/bin-win32/DOSBox-0.74/DOSBox.exe
/home/bin-win32/DOSBox-0.74/DOSBox.exe: PE32 executable (GUI) Intel 80386 (stripped to external PDB), for MS Windows

The build I made on ubuntu for debugging purpose

Program received signal SIGSEGV, Segmentation fault.
0x00000000004c876b in XGA_GetPoint (x=x@entry=18446744071562068601, y=y@entry=203) at vga_xga.cpp:179
179 return ((Bit32u*)(vga.mem.linear))[memaddr];
(gdb)
(gdb) backtrace
#0 0x00000000004c876b in XGA_GetPoint (x=x@entry=18446744071562068601, y=y@entry=203) at vga_xga.cpp:179
#1 0x00000000004c8b2b in XGA_DrawLineBresenham (val=<error reading variable: Cannot access memory at address 0x7fffffffa0a8>) at vga_xga.cpp:419
(gdb) q

Suggestion is to REMOVE the 64-bit DOSBox and replace it by a 32-bit version.

Status changed to 'Confirmed' because the bug affects multiple users.

I can now confirm that DOSBox works on 32-bit Ubuntu 14.04

@milasudril, are you talking about the same bug reported here? I.e. same segfault, happening when running 3D Studio R3. If not, please fill up a different bug report.

Then, if you're having trouble compiling dosbox from svn, that's an upstream bug and should be reported at the dosbox bugtracker (http://sourceforge.net/tracker/?group_id=52551&atid=467232) by following the instructions at http://vogons.zetafleet.com/viewtopic.php?t=2949.

@shankao: At least we are both stuck in XGA_DrawLineBresenham. Have you tried to run 3D Studio R3 on 32-bit system? I get the crash from within Windows 3.1, when it is issuing a LineTo GDI call (I draw this conclusion from the fact that it affect clock.exe (draws the handles) and a game called Stars (Draw line between two planets)). It does only happen on a 64-bit build of DOSBox. Since your trouble occurs on 64-bit, it might be a pointer size issue. I have seen really bad things in libxml2, that brakes down on x86-64 Windows. For example, there might be assumptions that

sizeof(unsigned int)==sizeof(void*)

I conclude that this is not a Ubuntu bug, but a DOSBox bug. The thing Ubuntu can do in the meantime is to provide a 32-bit binary package for DOSBox.I should tryout Windows 3.1 without the S3 driver. It would also be good to setup the same thing in Qemu+FreeDOS, if that supports emulation of the same graphics device. This will help to localize the bug.

If I run pure VGA, it does not crash. DOSBox S3 emulation is broken on a 64-bit build.

In the case of upstream bugs, the policy is to report it upstream (to the dosbox developers) and try to fix it there, not just for Ubuntu, but for the rest of people that uses dosbox. This is, unless it's a security bug or it's of high(er) importance. Please indicate us if you have already reported it there and a link to their bugtracker.

Then, for your request of the 32-bit package, Ubuntu supports to have 32 and 64 bit versions of packages installed side by side (multiarch). You can i.e. see this answer: http://askubuntu.com/questions/29665/how-do-i-apt-get-a-32-bit-package-on-a-64-bit-installation

Unbelievable that this is still an issue. I posted a patch: https://sourceforge.net/p/dosbox/patches/269/

@w3seek: that's nice, could you talk with the dosbox developers to get it merged there?

Looks like my patch was finally accepted last week.