gh-126220: Adapt _lsprof to Argument Clinic

Include/internal/pycore_global_strings.h

@@ -720,6 +720,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(strict_mode)
         STRUCT_FOR_ID(string)
         STRUCT_FOR_ID(sub_key)
+        STRUCT_FOR_ID(subcalls)
         STRUCT_FOR_ID(symmetric_difference_update)
         STRUCT_FOR_ID(tabsize)
         STRUCT_FOR_ID(tag)
@@ -737,8 +738,10 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(threading)
         STRUCT_FOR_ID(throw)
         STRUCT_FOR_ID(timeout)
+        STRUCT_FOR_ID(timer)
         STRUCT_FOR_ID(times)
         STRUCT_FOR_ID(timetuple)
+        STRUCT_FOR_ID(timeunit)
         STRUCT_FOR_ID(top)
         STRUCT_FOR_ID(trace_callback)
         STRUCT_FOR_ID(traceback)

Lib/test/test_cprofile.py

@@ -30,6 +30,22 @@ def test_bad_counter_during_dealloc(self):
 
             self.assertEqual(cm.unraisable.exc_type, TypeError)
 
+    def test_crash_on_no_args(self):
+        # gh-126220
+        import _lsprof
+
+        for profile in [_lsprof.Profiler(), cProfile.Profile()]:
+            for method in [
+                "_pystart_callback",
+                "_pyreturn_callback",
+                "_ccall_callback",
+                "_creturn_callback",
+            ]:
+                with self.subTest(profile=profile, method=method):
+                    method_obj = getattr(profile, method)
+                    with self.assertRaises(TypeError):
+                        method_obj()  # should not crash
+
     def test_evil_external_timer(self):
         # gh-120289
         # Disabling profiler in external timer should not crash

Misc/NEWS.d/next/Library/2024-10-31-14-06-28.gh-issue-126220.uJAJCU.rst

@@ -0,0 +1,2 @@
+Fix crash of ``cProfile.Profile`` and ``_lsprof.Profiler`` when their
+callbacks were directly called with 0 arguments.