forked from pool/python38
27 lines
1.1 KiB
Plaintext
27 lines
1.1 KiB
Plaintext
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Notes for packagers of Python3
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0. Faster build turnaround
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--------------------------
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By default, python builds with profile-guided optimization. This needs
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an additional run of the test suite and it is generally slow.
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PGO build takes around 50 minutes.
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For development, use "--without profileopt" option to disable PGO. This
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shortens the build time to ~5 minutes including test suite.
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1. import_failed.map
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----------------------
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This is a mechanism installed as part of python3-base, that places shim modules
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on python's path (through a generated zzzz-import-failed-hooks.pth file, so that
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it is imported as much at the end as makes sense; and an _import_failed subdir
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of /usr/lib/pythonX.Y). Then when the user tries to import a module that is part
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of a subpackage, the ImportError will contain a helpful message telling them
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which missing subpackage to install.
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This can sometimes cause problems on non-standard configurations, if the pth
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gets included too early (for instance if you are using a script to include all
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pths by hand in some strange order). Just something to look out for.
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