Question: Have you seen segfaults ever?

[joegaudet]

Been porting my python solver implementation over, and have been encountering segfaults on occasion?

Trying to figure out if it's my implementation or no.

[joegaudet]

Specifically seems to be occurring when I sum arrays of variables to apply constraints.

[ankane]

Hey @joegaudet, thanks for reporting. The library shouldn't segfault with any implementation, so seems like a bug.

What OS and Ruby version are you on? There have been some segfaults on CI with Ruby 3.2 and Ubuntu 22.04, but I haven't been able to reproduce locally with the same environment to figure out the cause.

[joegaudet]

Hey @ankane

• ruby 2.7.2
• or-tools (0.9.0)
• OS X ventura

[ankane]

Thanks, and which solver is it?

[joegaudet]

ORTools::CpModel

On Wed, Mar 8, 2023 at 4:28 PM Andrew Kane @.***> wrote:

Thanks, and which solver is it?

— Reply to this email directly, view it on GitHub https://github.com/ankane/or-tools-ruby/issues/44#issuecomment-1461078399, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAA6IB43DUGF67ZP6Q57ITTW3EPYFANCNFSM6AAAAAAVTJOUKE . You are receiving this because you were mentioned.Message ID: @.***>

[ankane]

Hey @joegaudet, can you try uninstalling the gem and using Rice from GitHub to see if that fixes it?

gem uninstall --all or-tools
bundle add rice --github jasonroelofs/rice
bundle install

It seems to make a difference on CI.

Ref: https://github.com/jasonroelofs/rice/pull/170

[ankane]

Hmm, using Rice from GitHub seems to make a difference on CI, even with the commit that matches the latest release, so don't think it's related to the referenced issue (also, doesn't appear to use that code path).

[ankane]

Quick update: Found a memory issue / the likely culprit - still working on how to solve.

[khadzhinov]

Hello, I got segmentation error on Ruby 2.6.5, Mac OS Ventura 13.6.1, and or-tools gem 0.3.4. I get this error, when I try to solve Time Window Constraints problem with wrong data (i.e. intersecting time windows), I found that on this ruby version and gem version the line solution = routing.solve(first_solution_strategy: :path_cheapest_arc) always returns me # object and then the line plan_output += "#{manager.index_to_node(index)} Time(#{solution.min(time_var)},#{solution.max(time_var)}) -> " raises segfault error, but when I try do the same on Ruby 3.0 and gem or-tools 0.11.1 routing.solve(first_solution_strategy: :path_cheapest_arc) returns me nil, and I can check that solution was not found and don't go further. So how can I get nil from that line, using 0.3.4 version of this gem, may be I need to change something, can you help me?

[BUG] Segmentation fault at 0x0000000000000010
ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-darwin18]

-- Crash Report log information --------------------------------------------
   See Crash Report log file under the one of following:                    
     * ~/Library/Logs/DiagnosticReports                                     
     * /Library/Logs/DiagnosticReports                                      
   for more details.                                                        
Don't forget to include the above Crash Report log file in bug reports.     

-- Control frame information -----------------------------------------------
c:0110 p:---- s:0783 e:000782 CFUNC  :min

[ankane]

Hi @khadzhinov, only the latest version is supported (which requires Ruby 3+).

Also, I'm no longer seeing the memory issue, fwiw.