ValueError: On entry to DGESDD parameter number 10 had an illegal value on riscv64

[olebole]

When testing sncosmo on a riscv64 machine (risc processor, 64 bit, little endian), I get the following failure:

_____________________ TestFitting.test_fitlc_arg_mutation ______________________

self = <sncosmo.tests.test_fitting.TestFitting object at 0x3fe802fb80>

    @pytest.mark.skipif('not HAS_IMINUIT')
    def test_fitlc_arg_mutation(self):
        """Test ``fit_lc`` does not mutate it's arguments"""
    
>       self._test_mutation(sncosmo.fit_lc)

sncosmo/tests/test_fitting.py:103: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
sncosmo/tests/test_fitting.py:86: in _test_mutation
    fit_func(test_data, test_model, test_vparams, bounds=test_bounds)
sncosmo/fitting.py:729: in fit_lc
    fitchisq = generate_chisq(fitdata, model, spectra, signature='iminuit',
sncosmo/fitting.py:37: in generate_chisq
    invcov = np.linalg.pinv(cov)
<__array_function__ internals>:5: in pinv
    ???
/usr/lib/python3/dist-packages/numpy/linalg/linalg.py:2002: in pinv
    u, s, vt = svd(a, full_matrices=False, hermitian=hermitian)
<__array_function__ internals>:5: in svd
    ???
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

a = array([[11987.55364268,     0.        ,     0.        , ...,
            0.        ,     0.        ,     0.        ],
...
       [    0.        ,     0.        ,     0.        , ...,
            0.        ,     0.        , 11987.55364268]])
full_matrices = False, compute_uv = True, hermitian = False

    @array_function_dispatch(_svd_dispatcher)
    def svd(a, full_matrices=True, compute_uv=True, hermitian=False):
        """…"""
        import numpy as _nx
        a, wrap = _makearray(a)
    
        if hermitian:
            […]
    
        _assert_stacked_2d(a)
        t, result_t = _commonType(a)
    
        extobj = get_linalg_error_extobj(_raise_linalgerror_svd_nonconvergence)
    
        m, n = a.shape[-2:]
        if compute_uv:
            if full_matrices:
                if m < n:
                    gufunc = _umath_linalg.svd_m_f
                else:
                    gufunc = _umath_linalg.svd_n_f
            else:
                if m < n:
                    gufunc = _umath_linalg.svd_m_s
                else:
                    gufunc = _umath_linalg.svd_n_s
    
            signature = 'D->DdD' if isComplexType(t) else 'd->ddd'
>           u, s, vh = gufunc(a, signature=signature, extobj=extobj)
E           ValueError: On entry to DGESDD parameter number 10 had an illegal value

/usr/lib/python3/dist-packages/numpy/linalg/linalg.py:1660: ValueError
----------------------------- Captured stderr call -----------------------------
init_dgesdd failed init

The same failure happens on TestFitting.test_mcmclc_arg_mutation, TestFitting.test_fit_lc, and TestFitting.test_flatten_result.
Full build/test log here.
On all other platforms, these tests pass.

Versions:

• Python 3.10.6
• sncosmo 2.8.0
• astropy 5.1
• numpy 1.21.5

[benjaminrose]

Googling, this seems to be an SVD issue in scipy, likely associated with inverting a matrix. I think it might be because these tests use noise free simulations. That is my first theory at least.

[olebole]

OK, thanks. Since Riscv64 is not an official Debian architecture yet, I would just do nothing here; so, there is no Riscv64 package of sncosmo in the moment, and once scipy fixes this, I'd retrigger the build.
Scipy version used in the build was 1.8.1.
Just for reference: do you have the corresponding Scipy issues?