numpy 2.5.5 - DepLog

2.5.42026-10-10T21:30:10Z

Release notes

Changes

# NumPy 2.5.4 Release Notes
Released on 2026-10-10.
NumPy 2.5.4 is a patch release that fixes bugs discovered after the 2.5.3
release. Highlights are:
Many typing fixes and improvements,
A workaround for the MSVC 19.51 bug, see below.
This release supports Python versions 3.12-3.15.

Improvements

numpy.linalg.svd and numpy.linalg.lstsq now raise for inputs containing
infinities instead of returning garbage results.
Fixed hangs in numpy.linalg.svd and numpy.linalg.lstsq for certain inputs
containing infinities for recent versions of some LAPACK implementations.
numpy.linalg.cond now handles non-finite inputs more consistently.
(gh-32593)

StringDType hashing with NaN sentinels

StringDType instances with equivalent floating-point NaN sentinels now
have equal hashes. Previously, distinct NaN objects could produce equal
dtype instances with different hashes, causing dictionary lookups and set
deduplication to fail.
(gh-32563)

MaskedArray resets a fill_value that cannot be represented in a new dtype

A fill_value copied from a source array is now reset to the default fill_value
for the new dtype when it cannot be represented in that dtype. Previously the
copied value could be stale: ufuncs that change dtype left the result holding a
fill_value typed for the old dtype, which raised a TypeError only when
something later validated it (such as .view()), and a floating point
fill_value that overflows an integer dtype was kept as an out-of-range value
together with a RuntimeWarning. Both now fall back to the default,
including when a masked array is passed to MaskedArray with a different
dtype. A fill_value given explicitly by the user is still validated and
raises as before. This can now raise a ComplexWarning if the fill_value is
complex and the new dtype is real.
(gh-32508)
(gh-32562)

Pull requests merged

A total of 17 pull requests were merged for this release.
#32520: MAINT: Prepare 2.5.x for further development
#32557: BUG: Reset an unrepresentable fill_value on a dtype change (#32508)
#32565: BLD: work around MSVC 19.51 bug (#32561)
#32600: BUG: fix np.strings.replace truncating old/new to a's
#32707: BUG: fix [ureduce]{#ureduce} reshape when a kept axis has size 0 (#32536)
#32709: BUG: fix two possible crashes in the ufunc.accumulate implementation...
#32710: BUG: Reset an inherited fill_value in MaskedArray.__new__ as...
#32711: ENH: Improvements and fixes for stringdtype hashing (#32563)
#32713: CI: increase ppc64le timeout to match other timeouts (#32583)
#32718: BUG: fix memory leak in legacy ArrayMethod wrapper code
#32719: BUG: check for non-finite input before calling gesdd/gelsd and...
#32738: BUG: fix segfault in as_arrays() on self-referencing pyscalars
#32741: TYP: Various typing improvements.
#32791: BUG: Fix canonicalization/promotion of nested subarray types...
#32888: MAINT: Update vendored-meson to match main.
#32904: TYP: Backport a number of typing updates.
#32956: TYP: Various typing fixes and improvements.

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