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)

Changes

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)

Contributors

A total of 9 people contributed to this release. People with a "+" by their
names contributed a patch for the first time.

• Aniket Singh Yadav
• Bhuvansh Kataria +
• Charles Harris
• Iason Krommydas
• Joren Hammudoglu
• Lazizbek Ergashev +
• Nathan Goldbaum
• Sebastian Berg
• Yeonho Kim

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.