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

[achalshah20]

Hi,
In your example cmake file I just added this line

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DNDEBUG")

and it breaks the program. I am getting error

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

Then I did "ldd example", and here is the result:

linux-vdso.so.1 => (0x00007ffe679b1000) libtensorflow_framework.so => /usr/lib/tensorflow_cc/libtensorflow_framework.so (0x00007f3ccb5d8000) libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f3ccb256000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f3ccb040000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f3ccac76000) libcublas.so.9.1 => /usr/local/cuda-9.1/lib64/libcublas.so.9.1 (0x00007f3cc7555000) libcuda.so.1 => /usr/lib/x86_64-linux-gnu/libcuda.so.1 (0x00007f3cc69b5000) libcudnn.so.7 => /usr/lib/x86_64-linux-gnu/libcudnn.so.7 (0x00007f3cb5a24000) libcufft.so.9.1 => /usr/local/cuda-9.1/lib64/libcufft.so.9.1 (0x00007f3cae537000) libcurand.so.9.1 => /usr/local/cuda-9.1/lib64/libcurand.so.9.1 (0x00007f3caa5b4000) libcudart.so.9.1 => /usr/local/cuda-9.1/lib64/libcudart.so.9.1 (0x00007f3caa346000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f3caa142000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f3ca9e39000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f3ca9c1c000) /lib64/ld-linux-x86-64.so.2 (0x00007f3ccc511000) librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f3ca9a14000) libnvidia-fatbinaryloader.so.390.30 => /usr/lib/nvidia-390/libnvidia-fatbinaryloader.so.390.30 (0x00007f3ca97c8000)

libtensorflow_cc.so is missing and if I remove -DNDEBUG flag, it works as expected. It might be issue from tensorflow compilation thing but I am not entirely sure. Can you please help me understand why -DNDEBUG is causing this problem? Thanks!

[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. :-)