Adding dlib's fft dependency

[KV2773]

Using the build.sh as

./build.sh -DCMAKE_POLICY_VERSION_MINIMUM=3.5   -DONNXRUNTIME_LIB_DIR=/usr/local/lib -DONNXRUNTIME_INCLUDE_DIR=/usr/local/include/onnxruntime  -DCMAKE_INSTALL_PREFIX=/usr/local -DOCOS_ENABLE_OPENCV_CODECS=OFF -DOCOS_ENABLE_VISION=OFF -DOCOS_ENABLE_AUDIO=OFF -DOCOS_ENABLE_CV2=OFF

Problem:

[ 96%] Linking CXX shared library lib/libortextensions.so
ld: 0711-317 ERROR: Undefined symbol: ._ZN4dlib3fftIfEEvRKNS_8fft_sizeEPKNSt3__17complexIT_EEPS7_b
ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more information.
.ibm-clang: error: linker command failed with exit code 8 (use -v to see invocation)
gmake[2]: *** [CMakeFiles/extensions_shared.dir/build.make:109: lib/libortextensions.so] Error 8
gmake[1]: *** [CMakeFiles/Makefile2:639: CMakeFiles/extensions_shared.dir/all] Error 2
gmake[1]: *** Waiting for unfinished jobs....
/home/Kushal/onnxruntime-1.20.0/aixoss/onnxruntime-extensions/test/static_test/test_ustring.cc:32:29: warning: 'codecvt_utf8<char32_t>' is deprecated [-Wdeprecated-declarations]

After my changes.

[ 92%] Linking CXX executable bin/ocos_test
[100%] Built target ocos_test
[100%] Built target extensions_test

[KV2773]

Hii @sayanshaw24 @skottmckay may you review it once.

[skottmckay]

Does it need the functions in fft.cpp or just the definition of fft_size?

What code requires an fft_size definition and how is that dependency resolved with a default build?

[skottmckay]

I would suggest adding something like this in the OCOS_ENABLE_MATH section before line 414 so that we only include the file when needed:

  # operators\math\energy_stft_segmentation.cc needs the dlib fft implementation
  list(APPEND TARGET_SRC ${TARGET_SRC_DLIB} ${dlib_SOURCE_DIR}/dlib/fft/fft.cpp)

onnxruntime-extensions/CMakeLists.txt

Line 414 in a9ec848

list(APPEND TARGET_SRC ${TARGET_SRC_MATH} ${TARGET_SRC_DLIB} ${TARGET_SRC_INVERSE})

And now as multiple places could include fft.cpp we should remove duplicates at the end of configuration just before the add_library around line 5196 That's simpler than multiple places checking whether a file has been added previously or not.

onnxruntime-extensions/CMakeLists.txt

Lines 516 to 517 in a9ec848

	add_library(noexcep_operators STATIC ${TARGET_SRC_NOEXCEPTION})
	add_library(ocos_operators STATIC ${TARGET_SRC})

list(REMOVE_DUPLICATES TARGET_SRC_NOEXCEPTION)
list(REMOVE_DUPLICATES TARGET_SRC)

[KV2773]

Does it need the functions in fft.cpp or just the definition of fft_size?

What code requires an fft_size definition and how is that dependency resolved with a default build?

So it needs the definition of fft_size only as per my observation.

This function is used by these files

grep_64: out/AIX/RelWithDebInfo/CMakeFiles/ocos_operators.dir/operators/math/math.cc.o: binary file matches

So in a default build we are making the OCOS_ENABLE_AUDIO by default on and in which we are adding this file fft.cpp which will give this definition.

if(OCOS_ENABLE_AUDIO)
  if (NOT OCOS_ENABLE_DLIB)
    message(FATAL_ERROR "Audio operators require DLIB to be enabled.")
  endif()
  include(dr_libs)
  file(GLOB TARGET_SRC_AUDIO "operators/audio/*.*")
  list(APPEND TARGET_SRC_AUDIO ${dlib_SOURCE_DIR}/dlib/fft/fft.cpp)
  list(APPEND TARGET_SRC_NOEXCEPTION ${TARGET_SRC_AUDIO})
endif()

[KV2773]

I would suggest adding something like this in the OCOS_ENABLE_MATH section before line 414 so that we only include the file when needed:

  # operators\math\energy_stft_segmentation.cc needs the dlib fft implementation
  list(APPEND TARGET_SRC ${TARGET_SRC_DLIB} ${dlib_SOURCE_DIR}/dlib/fft/fft.cpp)

onnxruntime-extensions/CMakeLists.txt

Line 414 in a9ec848

list(APPEND TARGET_SRC ${TARGET_SRC_MATH} ${TARGET_SRC_DLIB} ${TARGET_SRC_INVERSE})

And now as multiple places could include fft.cpp we should remove duplicates at the end of configuration just before the add_library around line 5196 That's simpler than multiple places checking whether a file has been added previously or not.

onnxruntime-extensions/CMakeLists.txt

Lines 516 to 517 in a9ec848

	add_library(noexcep_operators STATIC ${TARGET_SRC_NOEXCEPTION})
	add_library(ocos_operators STATIC ${TARGET_SRC})

list(REMOVE_DUPLICATES TARGET_SRC_NOEXCEPTION)
list(REMOVE_DUPLICATES TARGET_SRC)

Yep @skottmckay that way, also we can do, and your approach is better in that way.
Should I commit the changes or you will commit them.

[KV2773]

Hii @sayanshaw24 may u review it once.

[Copilot]

Pull request overview

This PR addresses an AIX link failure (Undefined symbol: dlib::fft<float>(...)) by ensuring dlib’s FFT implementation unit is compiled into the extensions build, even when audio operators are disabled.

Changes:

• Adds dlib/fft/fft.cpp to the CMake source list for builds where math ops are enabled.
• Minor whitespace cleanup around the ext_imgcodecs include.

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[KV2773]

Hii @skottmckay @sayanshaw24 may u review it once.