Fix for canonicalize segfault.

test/test_issue35.py

@@ -0,0 +1,38 @@
+import cdd
+import pytest
+
+
+def test_issue35_1() -> None:
+    mat = cdd.matrix_from_array([[0, 0, 0]], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_canonicalize(mat) == ({0}, set(), [None])
+    assert mat.array == []
+
+
+def test_issue35_2() -> None:
+    mat = cdd.matrix_from_array([[0, 0, 0]], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_redundancy_remove(mat) == ({0}, [None])
+    assert mat.array == []
+
+
+def test_issue35_3() -> None:
+    mat = cdd.matrix_from_array([[0, 0, 0]], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_canonicalize_linearity(mat) == ({0}, [None])
+    assert mat.array == []
+
+
+def test_issue35_4() -> None:
+    mat = cdd.matrix_from_array([], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_canonicalize(mat) == (set(), set(), [])
+    assert mat.array == []
+
+
+def test_issue35_5() -> None:
+    mat = cdd.matrix_from_array([], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_redundancy_remove(mat) == (set(), [])
+    assert mat.array == []
+
+
+def test_issue35_6() -> None:
+    mat = cdd.matrix_from_array([], rep_type=cdd.RepType.INEQUALITY)
+    assert cdd.matrix_canonicalize_linearity(mat) == (set(), [])
+    assert mat.array == []