[Build] Onnx runtime cross compilation with toolchain arm-linux-gnueabihf-9.1.0-gcc/g++ with reduced ops config failing

[work-dnd]

Describe the issue

I am trying to build a small footprint Onnx runtime cross compiled with toolchain arm-linux-gnueabihf-9.1.0-gcc/g++ just using required ops. Using my model.onnx I generated required_operators.config which has these ops -

ai.onnx;17;Flatten,Gemm,LayerNormalization,Relu,Sigmoid

Including this file, I started a minimul build with the attached build script. But the build failed due to the following error -

-- Build files have been written to: /path/to/onnxruntime-v1.20.1/build-arm/MinSizeRel
2025-04-02 21:31:09,473 build [INFO] - Building targets for MinSizeRel configuration
2025-04-02 21:31:09,473 build [INFO] - /usr/local/bin/cmake --build build-arm/MinSizeRel --config MinSizeRel -- -j8
[ 0%] Running cpp protocol buffer compiler (lite) on /path/to/onnxruntime-v1.20.1/build-arm/MinSizeRel/_deps/onnx-src/onnx/onnx-data.proto
[ 0%] Running cpp protocol buffer compiler (lite) on /path/to/onnxruntime-v1.20.1/build-arm/MinSizeRel/_deps/onnx-src/onnx/onnx-operators-ml.proto
[ 0%] Running cpp protocol buffer compiler (lite) on /path/to/onnxruntime-v1.20.1/build-arm/MinSizeRel/_deps/onnx-src/onnx/onnx-ml.proto

gmake[2]: /path/to/protoc-3.21.12: Permission denied
gmake[2]: *** [CMakeFiles/onnx_proto.dir/build.make:88: onnx/onnx-data.pb.h] Error 127
gmake[2]: *** Waiting for unfinished jobs....

I downloaded and used the protoc initially for cross-compiling full onnx runtime in the following way -

• found the version of prtotobuf for linux86_64 from cmake/deps.txt

• downloaded and extracted
  wget https://github.com/protocolbuffers/protobuf/releases/download/v21.12/protoc-21.12-linux-x86_64.zip

• updated the ONNX_CUSTOM_PROTOC_EXECUTABLE path with the extracted protoc

This worked fine in case of earlier complete cross-compilation. But it failed with --minimal_build extended

Even without --include_ops_by_config /path/to/equired_operators.config, I get the permission denied error

Tried providing permission with chmod +x , but did not work

Please help me resolve this issue. I can attach the full build log if required.

Urgency

I am tasked to deploy an onnx model in a very resource-constrained arm environment. Using a memory card, I tested the model with full onnx runtime libs and it executed as expected. But the libs all total required ~50 mb which is not available during deployment. But I am sure a lightweight runtime can be built for the reduced ops mentioned above.

Target platform

ARM

Build script

cd onnxruntime-v1.20.1
./build.sh
--config MinSizeRel
--arm
--parallel
--build_dir build-arm
--cmake_extra_defines CMAKE_TOOLCHAIN_FILE=/path/to/arm-linux-custom.cmake
--cmake_extra_defines ONNX_CUSTOM_PROTOC_EXECUTABLE=/path/to/protoc-3.21.12
--cmake_extra_defines onnxruntime_CROSS_COMPILING=ON
--skip_tests
--build_shared_lib
--minimal_build extended
--include_ops_by_config /path/to/required_operators.config \

Error / output

gmake[2]: /path/to/protoc-3.21.12: Permission denied
gmake[2]: *** [CMakeFiles/onnx_proto.dir/build.make:88: onnx/onnx-data.pb.h] Error 127
gmake[2]: *** Waiting for unfinished jobs....

Visual Studio Version

No response

GCC / Compiler Version

arm-linux-gnueabihf-9.1.0-gcc/g++

[snnn]

I am working on a fix.

[work-dnd]

Solved!

"--cmake_extra_defines ONNX_CUSTOM_PROTOC_EXECUTABLE=/path/to/protoc-3.21.12" - This line should be
--cmake_extra_defines ONNX_CUSTOM_PROTOC_EXECUTABLE=/path/to/protoc-3.21.12/bin/protoc (path upto protoc executable)