Segmentation fault when importing tensorflow before ortools

[youchangkim]

What version of OR-Tools and what language are you using?
Version: v9.3
Language: Python

Which solver are you using (e.g. CP-SAT, Routing Solver, GLOP, BOP, Gurobi)
CP-SAT

What operating system (Linux, Windows, ...) and version?
macOS BigSur x86-64

What did you do?

1. Download https://github.com/google/or-tools/blob/stable/ortools/sat/samples/simple_sat_program.py
2. Insert import tensorflow before from ortools.sat.python import cp_model

What did you expect to see

x = 1
y = 0
z = 0

What did you see instead?

Segmentation fault: 11

Anything else we should know about your project / environment

1. any tensorflow versions between v2.2.0 and v2.8.0 (available for py38) can reproduce the issue.
2. or-tools v9.2 works fine with any tensorflow versions.
3. importing tensorflow after ortools works fine.

[lperron]

It usually means that tf is linked with an older version of protobuf.

What happens if you import tf after or-tools ?

There is nothing we can do about it.

[Mizux]

related to:

• Importing tensorflow breaks ortools #2047

[youchangkim]

Tensorflow uses protobuf even older than what ortools v9.2 uses, but ortools v9.2 works fine. Was there any change in a way of linking protobuf in v9.3?

[youchangkim]

@Mizux This is slightly different from:

• Importing tensorflow breaks ortools #2047

because importing packages actually succeeded but segmentation fault happened during Solve.

Current thread 0x0000000118e9fdc0 (most recent call first):
  File "[REDACTED]/venv/lib/python3.7/site-packages/ortools/sat/python/cp_model.py", line 2168 in Solve

[youchangkim]

@lperron @Mizux Is it possible to do something similar to these?

• Make libprotobuf symbols local on OSX protocolbuffers/protobuf#8346
• Fix visibility of libprotobuf symbols in protoc_compiler.so on Mac grpc/grpc#24992

[youchangkim]

@Mizux Is there any plan to fix this in next release?

[Mizux]

For next release v9.4 no, I want to release it ASAP.
For v9.5 we can take a look and see if we can 1) easily reproduce the bug 2) fix it reusing the technique you suggest.

[lperron]

Yes, we bumped to 3.9.14. Nothing in our code has changed Le ven. 8 avr. 2022, 18:15, Youchang Kim ***@***.***> a écrit :

…

Tensorflow uses protobuf even older than what ortools v9.2 uses, but ortools v9.2 works fine. Was there any change in a way of linking protobuf in v9.3? — Reply to this email directly, view it on GitHub <#3230 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACUPL3NM2O4YZBCB7NHRS3LVEBLTDANCNFSM5S2IEV3A> . You are receiving this because you modified the open/close state.Message ID: ***@***.***>

[lperron]

Works fine now.