Merge "[HWASan] add comment to explain why we can use __has_feature" am: 26e0e00279 am: f04c163217 am: 8d60940a21 am: 28f93db5a7

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2636328

Change-Id: I7b4ef2fec7b4a16867214592bb5c1770205c2c66
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/libc/bionic/heap_tagging.cpp b/libc/bionic/heap_tagging.cpp
index be21e0c..230899a 100644
--- a/libc/bionic/heap_tagging.cpp
+++ b/libc/bionic/heap_tagging.cpp
@@ -208,6 +208,9 @@
   }
 #endif  // __aarch64__
 
+  // We can use __has_feature here rather than __hwasan_handle_longjmp as a
+  // weak symbol because this is part of libc which is always sanitized for a
+  // hwasan enabled process.
 #if __has_feature(hwaddress_sanitizer)
   __hwasan_handle_longjmp(sp_dst);
 #endif  // __has_feature(hwaddress_sanitizer)