[3.14] gh-140814: Fix freeze_support() setting start method as side effect (GH-144608)#146008
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gpshead merged 1 commit intopython:3.14from Mar 16, 2026
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…fect (pythonGH-144608) freeze_support() called get_start_method() without allow_none=True, which locked in the default start method context. This caused a subsequent set_start_method() call to raise "context has already been set". Use allow_none=True and accept None as a matching value, since spawn.freeze_support() independently detects spawned child processes. Test that freeze_support() does not lock in the default start method, which would prevent a subsequent set_start_method() call. (cherry picked from commit ee53180) Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com> Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
This was referenced Mar 16, 2026
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Mar 16, 2026
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freeze_support() called get_start_method() without allow_none=True,
which locked in the default start method context. This caused a
subsequent set_start_method() call to raise "context has already been
set". Use allow_none=True and accept None as a matching value, since
spawn.freeze_support() independently detects spawned child processes.
Test that freeze_support() does not lock in the default start method,
which would prevent a subsequent set_start_method() call.
(cherry picked from commit ee53180)
Co-authored-by: Gregory P. Smith 68491+gpshead@users.noreply.github.com
Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com
Co-authored-by: Bénédikt Tran 10796600+picnixz@users.noreply.github.com