Add clang lifetimebound section to developer notes

Author: jonatack

doc/developer-notes.md

@@ -32,6 +32,7 @@ Developer Notes
     - [C++ data structures](#c-data-structures)
     - [Strings and formatting](#strings-and-formatting)
     - [Shadowing](#shadowing)
+    - [Lifetimebound](#lifetimebound)
     - [Threads and synchronization](#threads-and-synchronization)
     - [Scripts](#scripts)
         - [Shebang](#shebang)
@@ -885,6 +886,16 @@ please name variables so that their names do not shadow variables defined in the
 When using nested cycles, do not name the inner cycle variable the same as in
 the outer cycle, etc.
 
+Lifetimebound
+--------------
+
+The [Clang `lifetimebound`
+attribute](https://clang.llvm.org/docs/AttributeReference.html#lifetimebound)
+can be used to tell the compiler that a lifetime is bound to an object and
+potentially see a compile-time warning if the object has a shorter lifetime from
+the invalid use of a temporary. You can use the attribute by adding a `LIFETIMEBOUND`
+annotation defined in `src/attributes.h`; please grep the codebase for examples.
+
 Threads and synchronization
 ----------------------------