gh-151524: Make it clearer that _PyInstrumentation_DISABLE is immortal in the code (GH-151525)

lpyu001 · web-flow · commit 52bed26b79cc · 2026-08-07T11:34:10.000-04:00
diff --git a/Python/instrumentation.c b/Python/instrumentation.c
@@ -989,8 +989,12 @@ call_one_instrument(
     if (res == NULL) {
         return -1;
     }
+    if (res == &_PyInstrumentation_DISABLE) {
+        assert(_Py_IsImmortal(res));
+        return 1;
+    }
     Py_DECREF(res);
-    return (res == &_PyInstrumentation_DISABLE);
+    return 0;
 }
 
 static const int8_t MOST_SIGNIFICANT_BITS[16] = {

Original file line number	Diff line number	Diff line change
`@@ -989,8 +989,12 @@ call_one_instrument(`
`989`	`989`	`if (res == NULL) {`
`990`	`990`	`return -1;`
`991`	`991`	`}`
	`992`	`+ if (res == &_PyInstrumentation_DISABLE) {`
	`993`	`+ assert(_Py_IsImmortal(res));`
	`994`	`+ return 1;`
	`995`	`+ }`
`992`	`996`	`Py_DECREF(res);`
`993`		`- return (res == &_PyInstrumentation_DISABLE);`
	`997`	`+ return 0;`
`994`	`998`	`}`
`995`	`999`
`996`	`1000`	`static const int8_t MOST_SIGNIFICANT_BITS[16] = {`