[issue28731] _PyDict_NewPresized() creates too small dict

[INADA Naoki]

New submission from INADA Naoki:

_PyDict_NewPresized(6) creates dict which keysize is 8.
But it's capacity is 5 (8 * 2 // 3 = 5).

This internal API is used by BUILD_MAP and BUILD_CONST_KEYMAP.

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assignee: inada.naoki
files: PyDict_NewPresized-too-small.patch
keywords: patch
messages: 281092
nosy: haypo, inada.naoki
priority: high
severity: normal
stage: patch review
status: open
title: _PyDict_NewPresized() creates too small dict
type: performance
versions: Python 3.6, Python 3.7
Added file: http://bugs.python.org/file45531/PyDict_NewPresized-too-small.patch

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue28731>
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