Fix for canonicalize segfault.

.github/workflows/build.yml

@@ -8,7 +8,7 @@ on:
     branches: [ develop ]
 
 env:
-  VCPKG_HASH: '5645ad4f3d73b652515ac8fdb50de70fdd331a34'
+  VCPKG_HASH: '08efacc0dcaf652c44de424befa1fe97c91a4896'
 
 jobs:
   build-sdist:
@@ -85,7 +85,7 @@ jobs:
       id: vcpkg-installed-cache
       with:
         path: installed/
-        key: vcpkg-1-${{ env.VCPKG_HASH }}-${{ matrix.os }}
+        key: vcpkg-0-${{ env.VCPKG_HASH }}-${{ matrix.os }}
     - uses: actions/checkout@v4
       if: steps.vcpkg-installed-cache.outputs.cache-hit != 'true'
       with:

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 == []