gh-148483: Use Py_GCC_ATTRIBUTE(unused) for stop_tracing label (GH-148481)

Author: clin1234

.gitignore

@@ -5,6 +5,7 @@
 *.cover
 *.iml
 *.o
+*.o.tmp
 *.lto
 *.a
 *.so

Misc/NEWS.d/next/Build/2026-04-13-02-36-13.gh-issue-148483.gLe1h8.rst

@@ -0,0 +1 @@
+Use ``Py_GCC_ATTRIBUTE(unused)`` for stop_tracing label.

Modules/_testinternalcapi/test_cases.c.h

@@ -203,6 +203,10 @@ def generate_tier1_labels(
     emitter.emit("\n")
     # Emit tail-callable labels as function defintions
     for name, label in analysis.labels.items():
+        if name == 'stop_tracing':
+            emitter.emit("#if _Py_TAIL_CALL_INTERP && !defined(_Py_TIER2)\n")
+            emitter.emit("Py_GCC_ATTRIBUTE((unused))\n")
+            emitter.emit("#endif\n")
         emitter.emit(f"LABEL({name})\n")
         storage = Storage(Stack(), [], [], 0, False)
         if label.spilled: