TST: mark float32 gges and qz tests as knownfail

See scipygh-16949

scipy/linalg/tests/test_decomp.py

@@ -10,6 +10,8 @@
 
 import itertools
 import platform
+import sys
+
 import numpy as np
 from numpy.testing import (assert_equal, assert_almost_equal,
                            assert_array_almost_equal, assert_array_equal,
@@ -2031,6 +2033,8 @@ class TestQZ:
     def setup_method(self):
         seed(12345)
 
+    @pytest.mark.xfail(sys.platform == 'darwin',
+        reason="gges[float32] broken for OpenBLAS on macOS, see gh-16949")
     def test_qz_single(self):
         n = 5
         A = random([n, n]).astype(float32)

scipy/linalg/tests/test_lapack.py

@@ -2,6 +2,7 @@
 # Created by: Pearu Peterson, September 2002
 #
 
+import sys
 from functools import reduce
 
 from numpy.testing import (assert_equal, assert_array_almost_equal, assert_,
@@ -3051,6 +3052,9 @@ def test_trexc_NAG(t, ifst, ilst, expect):
 
 @pytest.mark.parametrize('dtype', DTYPES)
 def test_gges_tgexc(dtype):
+    if dtype == np.float32 and sys.platform == 'darwin':
+        pytest.xfail("gges[float32] broken for OpenBLAS on macOS, see gh-16949")
+
     seed(1234)
     atol = np.finfo(dtype).eps*100
 
@@ -3220,6 +3224,9 @@ def test_trsen_NAG(t, q, select, expect, expect_s, expect_sep):
 
 @pytest.mark.parametrize('dtype', DTYPES)
 def test_gges_tgsen(dtype):
+    if dtype == np.float32 and sys.platform == 'darwin':
+        pytest.xfail("gges[float32] broken for OpenBLAS on macOS, see gh-16949")
+
     seed(1234)
     atol = np.finfo(dtype).eps*100