pycuda "nvcc fatal : Cannot find compiler 'cl.exe' in PATH"

Question

OS: win10

VS: visual stadio2015 64bit

CUDA: CUDA8.0

python: python2.7.12 64bit (pycuda)

I followed this website, https://documen.tician.de/pycuda/tutorial.html#getting-started

import  pycuda.driver as cuda
import pycuda.autoinit
from pycuda.compiler import SourceModule

import numpy

a = numpy.random.randn(4,4)
a = a.astype(numpy.float32)
a_gpu = cuda.mem_alloc(a.nbytes)
cuda.memcpy_htod(a_gpu,a)#transfer the data to the GPU

#executing a kernel
#function: write code to double each entry in a_gpu.
#we write the corresponding CUDA C code, and feed it into the constructor of pycuda.compiler.SourceModule
mod = SourceModule("""
    __global__ void doublify(float *a)
    {
        int idx = threadIdx.x + threadIdx.y*4;
        a[idx] *= 2;
    }
    """)

#If there aren’t any errors, the code is now compiled and loaded onto the device. We find a reference to our pycuda.driver.Function and call it, specifying a_gpu as the argument, and a block size of 4x4:
func = mod.get_function("doublify")
func(a_gpu, block=(4,4,1))

#Finally, we fetch the data back from the GPU and display it, together with the original a:
a_doubled = numpy.empty_like(a)
cuda.memcpy_dtoh(a_doubled, a_gpu)
print a_doubled
print a

but,failed with the error:

Traceback (most recent call last):
  File "G:/myworkspace/python2.7/cuda/test.py", line 24, in <module>
    """)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 265, in __init__
    arch, code, cache_dir, include_dirs)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 255, in compile
    return compile_plain(source, options, keep, nvcc, cache_dir, target)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 137, in compile_plain
    stderr=stderr.decode("utf-8", "replace"))
CompileError: nvcc compilation of c:\users\gl\appdata\local\temp\tmp8poxqp\kernel.cu failed
[command: nvcc --cubin -arch sm_50 -m64 -Id:\python2.7\lib\site-packages\pycuda\cuda kernel.cu]
[stdout:
nvcc fatal   : Cannot find compiler 'cl.exe' in PATH

]

Someone said to add the dir of cl.exe to environment. I did, and the error is the same. I'm new for CUDA. How could I solve this problem? Some advice?

I did as @citizenSNIPS adviced:

add the path to cl.exe, D:\vs2015\VC\bin.

INCLUDE = C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt.

LIB = C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\ucrt\x64(I can't find C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\um\x64 in my computer).

There had a new error as follow:

raceback (most recent call last):
  File "G:\myworkspace\python2.7\cuda\test.py", line 24, in <module>
    """)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 265, in __init__
    arch, code, cache_dir, include_dirs)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 255, in compile
    return compile_plain(source, options, keep, nvcc, cache_dir, target)
  File "D:\python2.7\lib\site-packages\pycuda\compiler.py", line 147, in compile_plain
    + (stdout+stderr).decode("utf-8", "replace"), stacklevel=4)
  File "D:\python2.7\lib\idlelib\run.py", line 36, in idle_showwarning_subproc
    message, category, filename, lineno, line))
  File "D:\python2.7\lib\idlelib\PyShell.py", line 65, in idle_formatwarning
    s += "%s: %s\n" % (category.__name__, message)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 147-168: ordinal not in range(128)

now I'm working for this problem, maybe it's because I did not add C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\um\x64?

Answer 1

you need to specify the path to cl.exe.

1. go to "Control Panel\All Control Panel Items\System" and select "advanced system settings"
2. select 'Environment Valiables'.

3. under system variables, find PATH, click edit, and add the path to cl.exe. it should be:

   C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\

Make sure when you installed visual studios, you selected to install c++ compiler. it is not installed by default. if you didn't, re-run your visual studio installer and select to install the c++ compiler.

once you finish with that, you might need to add the following system variables

INCLUDE = C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt
LIB = C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\um\x64
      C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\ucrt\x64

see this thread here

Answer 2

You could also have added the path to cl.exe in your python file. Downside is that you will have to change it if your MSVS version changes.

Example:

import os
if (os.system("cl.exe")):
    os.environ['PATH'] += ';'+r"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.11.25503\bin\HostX64\x64"
if (os.system("cl.exe")):
    raise RuntimeError("cl.exe still not found, path probably incorrect")

Edit: you need to run a MSVS version compatible with CUDA. I.e. CUDA v9.0 doesn't support MSVS2017 and CUDA v9.1 only supports version 15.4, not later versions. Try if it works by running nvcc.exe from the Native Tools Command Prompt for Visual Studio.

Answer 3

I add these code in .py

import sys
reload(sys)
sys.setdefaultencoding('utf8')

and run, there is no error