Hongru/cibuildwheel
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add section to the docs' FAQ about VC++ runtimes and VCRUNTIME140_1.dll on VS2019

Browse Source
This commit is contained in:
Yannick Jadoul
2020-08-28 01:52:04 +02:00
parent aafdff7ec7
commit fbb4e28b44
1 changed files with 8 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
docs/faq.md
+8
View File
@@ -61,3 +61,11 @@ python3 -m cibuildwheel --output-dir wheelhouse
python3 -m pip install twine
python3 -m twine upload wheelhouse/*.whl
```
### 'ImportError: DLL load failed: The specific module could not be found' error on Windows
Visual Studio and MSVC link the compiled binary wheels to the Microsoft Visual C++ Runtime. Normally, these are included with Python, but when compiling with a newer version of Visual Studio, it is possible users run into problems on system that do not have these runtime libraries installed. The solution is to download the corresponding Visual C++ Redistributable from the [Microsoft website](https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads).
Additionally, Visual Studio 2019 started linking to an even newer DLL, `VCRUNTIME140_1.dll`, besides the `VCRUNTIME140.dll` that is included with recent Python versions (starting from Python 3.5; see [here](https://wiki.python.org/moin/WindowsCompilers) for more details on the corresponding Visual Studio & MSVC versions used to compile the diffent Python versions). To avoid this extra dependency on `VCRUNTIME140_1.dll`, the [`/d2FH4-` flag](https://devblogs.microsoft.com/cppblog/making-cpp-exception-handling-smaller-x64/) can be added to the MSVC invocations (check out [this issue](https://github.com/joerick/cibuildwheel/issues/423) for details and references).
To investigate the dependecies of a C extension (i.e., the `.pyd` file, a DLL in disguise) on Windows, [Dependency Walker](http://www.dependencywalker.com/) is a great tool.