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`del` behavior on interpreter shutdown

See original GitHub issue

When finishing program execution, python does not guarantee the order in which objects are destroyed.

Calls inside a __del__ method calling other objects or modules are not guaranteed to be correctly executed.

https://github.com/cupy/cupy/blob/master/cupy/cuda/stream.pyx#L185 It is known to fail because runtime module is already unloaded when __del__ is called.

https://docs.python.org/3/reference/datamodel.html#object.__del__

This can affect behavior on RAII pattern.

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:9 (9 by maintainers)

Top GitHub Comments

1reaction

emcastillocommented, Dec 13, 2019

Installed manually

Conda flags

-I$CONDA_PREFIX/include/python3.7m 
-I$CONDA_PREFIX/include/python3.7m  
-Wno-unused-result 
-Wsign-compare 
-march=nocona 
-mtune=haswell 
-ftree-vectorize 
-fPIC 
-fstack-protector-strong 
-fno-plt 
-O3 
-ffunction-sections 
-pipe  
-fdebug-prefix-map=/tmp/build/80754af9/python_1553721932202/work=/usr/local/src/conda/python-3.7.3 -fdebug-prefix-map=$CONDA_PREFIX=/usr/local/src/conda-prefix 
-fuse-linker-plugin 
-ffat-lto-objects 
-flto-partition=none 
-flto 
-DNDEBUG 
-fwrapv 
-O3 
-Wall

Pyenv python 3.7.3 flags (python3-config --cflags)

-I$HOME/.pyenv/versions/3.7.3/include/python3.7m 
-I$HOME/.pyenv/versions/3.7.3/include/python3.7m  
-Wno-unused-result 
-Wsign-compare 
-DNDEBUG 
-g 
-fwrapv 
-O3 
-Wall

1reaction

emcastillocommented, Dec 13, 2019

We just found that if we install python with pyenv, then it breaks just with python -c 'import cupy; stream = cupy.cuda.Stream()' Credit goes to @niboshi

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