Repository navigation
[3.14] gh-160324: Keep io.StringIO state after MemoryError (GH-160325) - #161042
Merged
Merged
Conversation
…GH-160325) Allocate before consuming the accumulated writes in realize() and make_intermediate(), and reset the size when the contents are lost, so that later calls do not index outside the internal buffer. Shrink the buffer of the accumulating writer before finishing it, so that getvalue(), read() and the other methods leave the contents unchanged when they fail with MemoryError instead of dropping them. ANT-2026-MPHGX2FL (cherry picked from commit 83b047e) Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>
This was referenced Oct 31, 2026
gpshead
enabled auto-merge (squash)
October 31, 2026 23:10
gpshead
disabled auto-merge
November 9, 2026 00:28
They do not exist in 3.14. Use PyUnicode_Resize(), which leaves the buffer unchanged on failure, and update the writer fields directly.
In 3.14, writing a string to a new PyUnicodeWriter copies it, so a MemoryError there lost the contents of the StringIO. Disable overallocation for this write so the writer shares the string (copy-on-write) instead, as it does in main.
gpshead
approved these changes
Nov 9, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Allocate before consuming the accumulated writes in realize() and
make_intermediate(), and reset the size when the contents are lost,
so that later calls do not index outside the internal buffer.
Shrink the buffer of the accumulating writer before finishing it, so
that getvalue(), read() and the other methods leave the contents
unchanged when they fail with MemoryError instead of dropping them.
ANT-2026-MPHGX2FL
(cherry picked from commit 83b047e)
Co-authored-by: Gregory P. Smith 68491+gpshead@users.noreply.github.com
io.StringIOcrashes or returns garbage when used after aMemoryError#160324