Fix py312+ crash test skips to correctly check for assertions

src/greenlet/tests/test_tracing.py

@@ -1,15 +1,23 @@
 from __future__ import print_function
 import sys
+import sysconfig
 import greenlet
 import unittest
 
 from . import TestCase
 from . import PY312
 
 # https://discuss.python.org/t/cpython-3-12-greenlet-and-tracing-profiling-how-to-not-crash-and-get-correct-results/33144/2
-DEBUG_BUILD_PY312 = (
-    PY312 and hasattr(sys, 'gettotalrefcount'),
-    "Broken on debug builds of Python 3.12"
+# When build variables are available, OPT is the best way of detecting
+# the build with assertions enabled. Otherwise, fallback to detecting PyDEBUG
+# build.
+ASSERTION_BUILD_PY312 = (
+    PY312 and (
+        "-DNDEBUG" not in sysconfig.get_config_var("OPT").split()
+        if sysconfig.get_config_var("OPT") is not None
+        else hasattr(sys, 'gettotalrefcount')
+    ),
+    "Broken on assertion-enabled builds of Python 3.12"
 )
 
 class SomeError(Exception):
@@ -198,7 +206,7 @@ def run(self):
 
         self._check_trace_events_from_greenlet_sets_profiler(X(), tracer)
 
-    @unittest.skipIf(*DEBUG_BUILD_PY312)
+    @unittest.skipIf(*ASSERTION_BUILD_PY312)
     def test_trace_events_multiple_greenlets_switching(self):
         tracer = PythonTracer()
 
@@ -236,7 +244,7 @@ def g2_run():
             ('c_call', '__exit__'),
         ])
 
-    @unittest.skipIf(*DEBUG_BUILD_PY312)
+    @unittest.skipIf(*ASSERTION_BUILD_PY312)
     def test_trace_events_multiple_greenlets_switching_siblings(self):
         # Like the first version, but get both greenlets running first
         # as "siblings" and then establish the tracing.