[Bug]: examples/cpp/executor linking failure

[WilliamTambellini]

System Info

TRTLLM: today's main commit 81fd468
TRT: 10.11
cuda: 12.9
GCC: 11.3
OS: rocky8.10

Who can help?

@tongyuantongyu

Information

• The official example scripts
• My own modified scripts

Tasks

• An officially supported task in the examples folder (such as GLUE/SQuAD, ...)
• My own task or dataset (give details below)

Reproduction

1 cd cpp/build && cmake -DUSE_CXX11_ABI=OFF ..
2 make
3 cd ../../examples/cpp/executor/build
4 cmake ..
5 make

Expected behavior

Build success

actual behavior

Linking failure:

[ 10%] Building CXX object CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o                                                                                       
g++ -DENABLE_BF16 -DENABLE_FP8 -Iexamples/cpp/executor/../../../cpp/include 
-isystem /usr/local/cuda-12/include -Wall -pthread -lstdc++ -DENABLE_MULTI_DEVICE=0  -O3 
-std=gnu++17 
-D_GLIBCXX_USE_CXX11_ABI=1 
-MD -MT  CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o 
-MF CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o.d 
-o CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o -c 
/local/wtambellini/TensorRT-LLM/examples/cpp/executor/executorExampleBasic.cpp         

[ 20%] Linking CXX executable executorExampleBasic                                                                                                                              
cmake -E cmake_link_script CMakeFiles/executorExampleBasic.dir/link.txt --verbose=1                           
g++ -Wall -pthread -lstdc++ -DENABLE_MULTI_DEVICE=0  -O3 CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o -o executorExampleBasic  libnvinfer_plugin_tensorrt_llm.so libtensorrt_llm.so /usr/lib64/libcuda.so /usr/local/cuda-12.9/targets/x86_64-linux/lib/libcudart_static.a -lpthread -ldl /usr/lib64/librt.so /usr/lib64/libnvidia-ml.so
                                 
CMakeFiles/executorExampleBasic.dir/executorExampleBasic.cpp.o: In function `main':                                                                                             
executorExampleBasic.cpp:(.text.startup+0x375): undefined reference to 
`tensorrt_llm::executor::Executor::Executor(std::filesystem::__cxx11::path const&, 
tensorrt_llm::executor::ModelType, tensorrt_llm::executor::ExecutorConfig const&)'                                                                                                                    
...

See that _GLIBCXX_USE_CXX11_ABI has been set to 1

additional notes

It s because the example executor cmake script tries to auto guess if cxx11ABI was on in libtensorrt_llm.so:

TensorRT-LLM/examples/cpp/executor/CMakeLists.txt

Line 41 in 81fd468

COMMAND bash -c "nm -f posix -D ${TRTLLM_LIB_PATH} | grep __cxx11"

Despite building without cxx11 ABI, my libtensorrt_llm.so still has a small dozen of 'cxx11' keywords in some symbols:

$ nm -f posix -D cpp/Release/tensorrt_llm/libtensorrt_llm.so | grep __cxx11                                  
_ZN12tensorrt_llm6common14printArrayInfoI13__nv_bfloat16EEvPKT_mNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEb W 00000000045005e0 0000000000000d88
...

When I force set USE_CXX11_ABI=0, the examples link fine.

Proposal:
I propose to just add a cmake option to examples/cpp/executor/CMakeLists.txt in order for the user to let the script autodetects USE_CXX11_ABI or not.
Example:

option(AUTODETECT_USE_CXX11_ABI ON)
if(${AUTODETECT_USE_CXX11_ABI})
 execute_process(
   COMMAND bash -c "nm -f posix -D ${TRTLLM_LIB_PATH} | grep __cxx11"
  RESULT_VARIABLE GLIB_CXX11_FOUND
  OUTPUT_QUIET)
if(GLIB_CXX11_FOUND EQUAL 0)
  set(USE_CXX11_ABI 1)
else()
  set(USE_CXX11_ABI 0)
endif()
endif()

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[Shixiaowei02]

Thanks for your contribution!

[karljang]

Closing this as stale: examples/cpp/executor was removed in #16369 along with the legacy TensorRT backend, so this build no longer exists. Thanks for your contribution though!