address clanker review comments

Author: scottgerring

libdd-profiling-heap-sampler/include/datadog/heap/probes.h

@@ -31,16 +31,15 @@
  */
 void dd_probe_alloc(void *user, uint64_t size, uint64_t weight);
 
-#if DD_HEAP_LIVE_TRACKING
 /*
  * Emits the `ddheap:free` USDT.
  *   ptr - user-visible pointer being freed
  *
- * Only available when compiled with live-heap tracking. The absence of
- * the `ddheap:free` note in .note.stapsdt signals to external profilers
- * that this binary does not support live-heap correlation.
+ * The symbol always exists, but the USDT is only emitted when compiled
+ * with live-heap tracking. The absence of the `ddheap:free` note in
+ * .note.stapsdt signals to external profilers that this binary does not
+ * support live-heap correlation.
  */
 void dd_probe_free(void *ptr);
-#endif
 
 #endif

libdd-profiling-heap-sampler/src/probes.c

@@ -23,8 +23,10 @@ void dd_probe_alloc(void *user, uint64_t size, uint64_t weight) {
     USDT(ddheap, alloc, user, size, weight);
 }
 
-#if DD_HEAP_LIVE_TRACKING
 void dd_probe_free(void *ptr) {
+#if DD_HEAP_LIVE_TRACKING
     USDT(ddheap, free, ptr);
-}
-#endif
+#else
+    (void)ptr;
+#endif
+}