[3.14] Skip test_highly_nested_objects_decoding during the PGO profile task. (GH-151460)#151469
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…pythonGH-151460) Since the recursion guard tracks real C-stack bounds (pythongh-91079), this test asserts that 500k nesting levels overflow the stack margin. On a 64 MiB stack (some Nix build envs use one that large), the optimized interpreter uses ~160 bytes/level (raises at ~420k levels) so the assertion holds with only ~16% margin; the PGO *instrumented* stage inlines less, its per-level scanner frames are smaller, and the 500k-deep decode completes -- "RecursionError not raised" fails the profile run and aborts `make profile-opt`. Upstream's skip_if_unlimited_stack_size (pythongh-143460) only covers RLIM_INFINITY, not large-finite stacks like ours. We could also keep playing whack a mole and raise the 500k to a much larger number... but there's little value in PGO training on this test anyways. (cherry picked from commit e91f68a) Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>
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Since the recursion guard tracks real C-stack bounds (gh-91079), this test
asserts that 500k nesting levels overflow the stack margin. On a 64 MiB stack
(some Nix build envs use one that large), the optimized interpreter uses ~160
bytes/level (raises at ~420k levels) so the assertion holds with only ~16%
margin; the PGO instrumented stage inlines less, its per-level scanner frames
are smaller, and the 500k-deep decode completes -- "RecursionError not raised"
fails the profile run and aborts
make profile-opt. Upstream'sskip_if_unlimited_stack_size (gh-143460) only covers RLIM_INFINITY, not
large-finite stacks like ours.
We could also keep playing whack a mole and raise the 500k to a much larger
number... but there's little value in PGO training on this test anyways.
(cherry picked from commit e91f68a)
Co-authored-by: Gregory P. Smith 68491+gpshead@users.noreply.github.com