debug test for Windows crash...

Author: oscarbenjamin

src/flint/test/test_all.py

@@ -4195,6 +4195,10 @@ def test_matrices_rref():
 
 def test_matrices_fflu():
 
+    A = flint.fmpz_mat([[1, 2], [3, 4]])
+    P, L, D, U = A.fflu()
+    return
+
     QQ = flint.fmpq_mat
     shape = lambda A: (A.nrows(), A.ncols())