Error LNK2001, for symbol state in C extension.

[Qinka]

• OS: Windows 10
• PyTorch version: master( '0.4.0a0+0de5443')
• How you installed PyTorch (conda, pip, source): source
• Python version: Python 3.6.3 |Anaconda custom (64-bit)| (default, Oct 15 2017, 03:27:45) [MSC v.1900 64 bit (AMD64)] on win32
• CUDA/cuDNN version: CUDA-9.0
• GPU models and configuration:
• VS 2015(v140 toolset)
  When trying to compile C extension, linked with ATen, I got an error: can not found symbol state(error LNK2001).

And the librarys, THx are not compiled.

[peterjc123]

Changes the source code from C to C++. An example is listed below.

#include <THC/THC.h>
#include <ATen/ATen.h>

ATen_CLASS at::Context &at::globalContext();
THCState *state = at::globalContext().thc_state;

extern "C" int my_lib_add_forward_cuda(THCudaTensor *input1, THCudaTensor *input2,
                                       THCudaTensor *output)
{
  if (!THCudaTensor_isSameSizeAs(state, input1, input2))
    return 0;
  THCudaTensor_resizeAs(state, output, input1);
  THCudaTensor_cadd(state, output, input1, 1.0, input2);
  return 1;
}

extern "C" int my_lib_add_backward_cuda(THCudaTensor *grad_output, THCudaTensor *grad_input)
{
  THCudaTensor_resizeAs(state, grad_input, grad_output);
  THCudaTensor_fill(state, grad_input, 1);
  return 1;
}

[Qinka]

@peterjc123 I found ATen_CLASS is undefined, and codes can be compiled after removing it.

[Qinka]

So how to control the build type of MSVS. When building extension, what should I do if I what to build it in Debug mode.

[peterjc123]

@Qinka According to this post, you should add /ZI flag for debug version.

[li91yang]

When trying to compile C extension, I got error( VerificationError: CompileError: command 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\x86_amd64\cl.exe' failed with exit status 2), and tried all the methods mentioned, but all can't fix it. Is there anyone know how to fix it?
OS: Windows 10
PyTorch version: 0.4.1
How you installed PyTorch (conda, pip, source): conda
Python version: Python 3.5.6 |Anaconda, Inc.| (default, Aug 26 2018, 16:05:27) [MSC v.1900 64 bit (AMD64)] on win32
CUDA/cuDNN version: CUDA-9.0
GPU models and configuration: VS 2015

generating C:\Users\liyang\AppData\Local\Temp\tmp65k1yok8_my_lib.c
setting the current directory to 'C:\Users\liyang\AppData\Local\Temp\tmp65k1yok8'
running build_ext
building '_my_lib' extension
creating Release
creating Release\models
creating Release\models\ops
creating Release\models\ops\learn
creating Release\models\ops\learn\11
creating Release\models\ops\learn\11\src
C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\x86_amd64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -IC:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi....\lib\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi....\lib\include\TH -IC:\Users\liyang\Anaconda3\pkgs\pytorch-cpu-0.4.1-py35_cpuhe774522_1\Lib\site-packages\torch\lib\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\include "-IC:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE" "-IC:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\ATLMFC\INCLUDE" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\ucrt" "-IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\include\um" "-IC:\Program Files (x86)\Windows Kits\8.1\include\shared" "-IC:\Program Files (x86)\Windows Kits\8.1\include\um" "-IC:\Program Files (x86)\Windows Kits\8.1\include\winrt" /Tc_my_lib.c /Fo.\Release_my_lib.obj -std=c99
C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\x86_amd64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -IC:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi....\lib\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi....\lib\include\TH -IC:\Users\liyang\Anaconda3\pkgs\pytorch-cpu-0.4.1-py35_cpuhe774522_1\Lib\site-packages\torch\lib\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\include -IC:\Users\liyang\Anaconda3\envs\pytorch41\include "-IC:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE" "-IC:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\ATLMFC\INCLUDE" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\ucrt" "-IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\include\um" "-IC:\Program Files (x86)\Windows Kits\8.1\include\shared" "-IC:\Program Files (x86)\Windows Kits\8.1\include\um" "-IC:\Program Files (x86)\Windows Kits\8.1\include\winrt" /EHsc /TpI:\D435\DepthCNN\models\ops\learn\11\src\my_lib.cpp /Fo.\Release\D435\DepthCNN\models\ops\learn\11\src\my_lib.obj -std=c99
Traceback (most recent call last):

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 668, in runfile
execfile(filename, namespace)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 108, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)

File "I:/models/ops/learn/11/build.py", line 38, in
ffi.build()

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi_init_.py", line 189, in build
_build_extension(ffi, cffi_wrapper_name, target_dir, verbose)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\torch\utils\ffi_init_.py", line 111, in _build_extension
outfile = ffi.compile(tmpdir=tmpdir, verbose=verbose, target=libname)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\cffi\api.py", line 697, in compile
compiler_verbose=verbose, debug=debug, **kwds)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\cffi\recompiler.py", line 1520, in recompile
compiler_verbose, debug)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\cffi\ffiplatform.py", line 22, in compile
outputfilename = _build(tmpdir, ext, compiler_verbose, debug)

File "C:\Users\liyang\Anaconda3\envs\pytorch41\lib\site-packages\cffi\ffiplatform.py", line 58, in _build
raise VerificationError('%s: %s' % (e.class.name, e))

VerificationError: CompileError: command 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\x86_amd64\cl.exe' failed with exit status 2

[podgorskiy]

@peterjc123, thanks that helped me!

The part:

ATen_CLASS at::Context &at::globalContext();
THCState *state = at::globalContext().thc_state;

With current pytorch version, should be

THC_CLASS at::Context& at::globalContext();
THCState *state = at::globalContext().getTHCState();

[peterjc123]

Closing this, as it is not supported anymore.