Update Documentation for Emscripten Builds #1621
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* update emsdk version information * link to `Tools/wasm/README.md` for usage instructions beyond what's shown here * add note about ccache * add note about minimum Python version for `Tools/wasm/emscripten build`
| ``Tools/wasm/emscripten build`` command (which should be run with a recent | ||
| version of Python you have installed on your machine): | ||
| ``Tools/wasm/emscripten build`` command, which should be run with a recent | ||
| version of Python (3.13 or newer) already installed on your machine: | ||
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| .. code-block:: shell |
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I can't comment on he code block below - but there's now one more build step - make-mpdec (same general structure as the make-libffi call).
As a longer term maintenance issue, this list of subcommands is likely to change over time; the dev guide should always have the instructions for the current state of main, but it might be worth flagging that some of the steps might not exist on older Python versions.
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Ah, right. I missed that change. I'll update the code block to match the current steps.
That addition looks like it was backported to 3.14, so maybe not an urgent question, but I do agree that it's worth thinking through how best to label version-specific steps.
It would be great to have this generated automatically, but I'm not sure how best to do that (you could imagine adding a command to Tools/wasm/emscripten that outputs these steps rather than hard-coding them in the dev guide, but that doesn't feel particularly great). For now I'll just update the list of commands here.
getting-started/setup-building.rst
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| CPython you're building: | ||
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| * For building CPython 3.14, use ``emsdk`` version ``4.0.11``. | ||
| * For building CPython 3.13, use ``emsdk`` version ``4.0.5``. |
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I know this isn't correct... but I don't know what is correct. I'm fairly certian it's 3.something...
However, it might be better to leave this line off entirely. Emscripten isn't Tier 3 for 3.13. Having specific build instructions implies (to me) that it should work, and that definitely won't be the case.
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That sounds good to me; sorry for the error! Makes sense only to include it for 3.14+.
| It is possible (but not necessary) to enable ``ccache`` for Emscripten builds | ||
| by setting the ``EM_COMPILER_WRAPPER`` environment, but this step will only | ||
| take effect if it is done **after** ``emsdk_env.sh`` is sourced (otherwise, the | ||
| sourced script removes the environment variable): |
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@hoodmane This was the historical guidance for ccache... is it still required now that the --config-cache option is part of the emscripten build script?
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I'll review this tomorrow. Thanks @adqm ! |
This patch includes some updates to the instructions for building for Emscripten, based on discussion from python/cpython#137312 and python/cpython#137025, with the goal of reducing duplicated information between the dev guide and
Tools/wasm/README.mdin the CPython repo.Specifically, this patch makes the following changes:
updates emsdk version information
links to
Tools/wasm/README.mdfor usage instructions beyond what's shown hereadds a note about ccache
adds a note about minimum Python version required for
Tools/wasm/emscripten build📚 Documentation preview 📚: https://cpython-devguide--1621.org.readthedocs.build/