Merge pull request astropy#16581 from neutrinoceros/io.fits/bug/16578…

…/skip_windows_hack_on_numpy2

BUG: skip un-portable hack on windows + numpy2

astropy/io/fits/hdu/hdulist.py

@@ -24,6 +24,7 @@
 )
 from astropy.io.fits.verify import VerifyError, VerifyWarning, _ErrList, _Verify
 from astropy.utils import indent
+from astropy.utils.compat.numpycompat import NUMPY_LT_2_0
 
 # NOTE: Python can be built without bz2.
 from astropy.utils.compat.optional_deps import HAS_BZ2
@@ -1506,7 +1507,7 @@ def _flush_resize(self):
                     del hdu.data
                 hdu._file = ffo
 
-            if sys.platform.startswith("win"):
+            if sys.platform.startswith("win") and NUMPY_LT_2_0:
                 # On Windows, all the original data mmaps were closed above.
                 # However, it's possible that the user still has references to
                 # the old data which would no longer work (possibly even cause
@@ -1517,6 +1518,8 @@ def _flush_resize(self):
                 # lead to odd behavior in practice.  Better to just not keep
                 # references to data from files that had to be resized upon
                 # flushing (on Windows--again, this is no problem on Linux).
+                # Note that this hack is only possible on numpy 1.x:
+                # in 2.x, we cannot write directly to the data attribute
                 for idx, mmap, arr in mmaps:
                     if mmap is not None:
                         # https://github.com/numpy/numpy/issues/8628

docs/changes/io.fits/16581.bugfix.rst

@@ -0,0 +1,5 @@
+Fixed a crash that occurred for files opened via
+``fits.open(..., mode='update')``, on Windows, and with numpy 2.0 installed.
+It is possible, though unlikely, that this patch reveals memory issues
+for downstream code run under these exact conditions. Please report any
+regression found.

pyproject.toml

@@ -40,8 +40,6 @@ keywords = [
 ]
 dependencies = [
     "numpy>=1.23",
-    # https://github.com/astropy/astropy/issues/16578
-    "numpy < 2.0 ; platform_system=='Windows'",
     "pyerfa>=2.0.1.1",
     "astropy-iers-data>=0.2024.5.27.0.30.8",
     "PyYAML>=3.13",