pytorch - 💡(How to fix) Fix torch::stable::Device(const std::string&) linker error [3 comments, 2 participants]

/usr/bin/ld: stabledevice.o: in function make_device_broken(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)': stabledevice.cpp:25: undefined reference to torch::stable::Device::Device(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /usr/bin/ld: build/lib.linux-x86_64-cpython-312/stabledevice.cpython-312-x86_64-linux-gnu.so: hidden symbol `_ZN5torch6stable6DeviceC1ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE' isn't defined /usr/bin/ld: final link failed: bad value collect2: error: ld returned 1 exit status

TL;DR

The issue can be resolved by using the torch::stable::Device constructor that takes a torch::DeviceType and an index, instead of the constructor that takes a std::string.

Guidance

• The error message indicates an undefined reference to the torch::stable::Device constructor that takes a std::string, suggesting that this constructor is not available for use in out-of-tree extensions.
• The Torch implementation of torch::stable::Device provides a constructor that takes a torch::DeviceType and an index, which can be used instead of the constructor that takes a std::string.
• To fix the issue, modify the make_device_broken function to use the available constructor, for example by passing torch::headeronly::kCUDA and an index.
• Verify that the modified code compiles and links successfully.

Example

torch::stable::Device make_device_broken() {
  return torch::stable::Device(torch::headeronly::kCUDA, 0);
}

Notes

• The issue is specific to Torch 2.11.0 and may not apply to other versions.
• The availability of certain constructors may vary depending on the Torch version and the type of extension being built.

Recommendation

Apply workaround: The recommended solution is to modify the code to use the available constructor, as shown in the example above. This workaround allows the code to compile and link successfully, while avoiding the use of the unavailable constructor.