Fix fallback implementation for pg_atomic_test_set_flag().

nathan-bossart · nathan-bossart · commit c23677844c96 · 2023-11-15T15:04:47.000-06:00
The fallback implementation of pg_atomic_test_set_flag() that uses atomic-exchange gives pg_atomic_exchange_u32_impl() an extra argument. This issue has been present since the introduction of the atomics API in commit b64d92f. Reviewed-by: Andres Freund Discussion: https://postgr.es/m/20231114035439.GA1809032%40nathanxps13 Backpatch-through: 12
diff --git a/src/include/port/atomics/generic.h b/src/include/port/atomics/generic.h
@@ -83,7 +83,7 @@ pg_atomic_init_flag_impl(volatile pg_atomic_flag *ptr)
 static inline bool
 pg_atomic_test_set_flag_impl(volatile pg_atomic_flag *ptr)
 {
-	return pg_atomic_exchange_u32_impl(ptr, &value, 1) == 0;
+	return pg_atomic_exchange_u32_impl(ptr, 1) == 0;
 }
 
 #define PG_HAVE_ATOMIC_UNLOCKED_TEST_FLAG

Original file line number	Diff line number	Diff line change
`@@ -83,7 +83,7 @@ pg_atomic_init_flag_impl(volatile pg_atomic_flag *ptr)`
`83`	`83`	`static inline bool`
`84`	`84`	`pg_atomic_test_set_flag_impl(volatile pg_atomic_flag *ptr)`
`85`	`85`	`{`
`86`		`- return pg_atomic_exchange_u32_impl(ptr, &value, 1) == 0;`
	`86`	`+ return pg_atomic_exchange_u32_impl(ptr, 1) == 0;`
`87`	`87`	`}`
`88`	`88`
`89`	`89`	`#define PG_HAVE_ATOMIC_UNLOCKED_TEST_FLAG`