Windows CI failing

[WarrenWeckesser]

The Windows CI jobs has been failing for a long time (since April?). In my recent PR, the start of the list of failures is

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
scipy_special_tests_test_cyl_bessel_y.exe is a Catch2 v3.8.0 host application.
Run with -? for options

-------------------------------------------------------------------------------
cyl_bessel_y dD->D scipy_special_tests
-------------------------------------------------------------------------------
D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(27)
...............................................................................

D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(42): FAILED:
  REQUIRE( error <= tol )
with expansion:
  inf <= 0.00000000000000711
with messages:
  v := -0.0
  z := (0,0)
  out := (-inf,-nan(ind))
  desired := (-inf,0)
  error := inf
  tol := 0.00000000000000711
  fallback := false

-------------------------------------------------------------------------------
cyl_bessel_y dD->D scipy_special_tests
-------------------------------------------------------------------------------
D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(27)
...............................................................................

D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(42): FAILED:
  REQUIRE( error <= tol )
with expansion:
  inf <= 0.00000000000000711
with messages:
  v := -0.0
  z := (0,0)
  out := (-inf,-nan(ind))
  desired := (-inf,0)
  error := inf
  tol := 0.00000000000000711
  fallback := false

-------------------------------------------------------------------------------
cyl_bessel_y dD->D scipy_special_tests
-------------------------------------------------------------------------------
D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(27)
...............................................................................

D:\a\xsf\xsf\tests\scipy_special_tests\test_cyl_bessel_y.cpp(42): FAILED:
  REQUIRE( error <= tol )
with expansion:
  inf <= 0.00000000000000711
with messages:
  v := -0.76923076923076927
  z := (0,0)
  out := (inf,-nan(ind))
  desired := (inf,0)
  error := inf
  tol := 0.00000000000000711
  fallback := false

...

There are many more.

It looks like the failures are with edges cases, such as

  out := (inf,-nan(ind))
  desired := (inf,0)

and

  out := (-nan(ind),-nan(ind))
  desired := (-inf,inf)

and

  out := (nan,nan)
  desired := (inf,-inf)

etc.

Is the underlying problem already known?

[lucascolley]

not sure on the exact status but to help traceability, #21 (comment) was some early discussion related to Windows