DNDEBUG flag in cmake doesn't link libtensorflow_cc.so file about tensorflow_cc

[FloopCZ]

Hi, this behavior is strange, but I don't really know what is wrong. Fortunately, you don't need to use NDEBUG macro, since tensorflow is already configured for optimized build here.

[FloopCZ]

Sorry, you are talking about the example CMakeLists, not the tensorflow_cc CMakeLists. That may cause some issues. Can you please try to build the example with -DCMAKE_BUILD_TYPE=Release and tell me whether it produces the same error?

[achalshah20]

Thanks!

So, I did following steps

cd example  

mkdir build  

cd build  

cmake -DCMAKE_BUILD_TYPE=Release  

make -j  

Then I did "ldd example" and I couldn't find the libtensorflow_cc.so file but it can find libtensorflow_framework.so. Moreover, the same error if I execute ./example.

"No session factory registered for the given session options: {target: "" config: } Registered factories are {}."

I am not able to understand how -DNDEBUG flag affects the library linking part!?

[FloopCZ]

Hi, thank you. I was looking into it, but unfortunately, I have not been able to solve it.

Tensorflow uses global register objects. I believe the problem is that without the NDEBUG symbol, the global register objects that appear to be unused get optimized out by the compiler. Unfortunately, I have no idea how to avoid it.

Does anyone have a suggestion?

Relevant issues: tensorflow/tensorflow#3308 tensorflow/tensorflow#6396 tensorflow/tensorflow#4242

[FloopCZ]

@achalshah20 It appears that monolithic build solves the issue, can you please try #64, whether it helps you as well?

[achalshah20]

Hi @FloopCZ , Yes it works. Thanks for the fix!
I am still wondering what monolithic build has to do with debug flags?

[FloopCZ]

Monolithic build merges all the libraries into a single library libtensorflow_cc.so (i.e., no extra libtensorflow_framework.so). This single library has to be linked, so we avoid optimizing out the global registers. It is a little bit hacky, though. :-)