``test/Bitcode/compatibility.ll``.
* The bitcode format produced by a X.Y release will be readable by all
- following X.Z releases and the (X+1).0 release. To help ensure this, an X.Y
- version of ``test/Bitcode/compatibility.ll`` should be assembled and
- committed after each release.
+ following X.Z releases and the (X+1).0 release.
+
+* After each X.Y release, ``compatibility.ll`` must be copied to
+ ``compatibility-X.Y.ll``. The corresponding bitcode file should be assembled
+ using the X.Y build and committed as ``compatibility-X.Y.ll.bc``.
* Newer releases can ignore features from older releases, but they cannot
miscompile them. For example, if nsw is ever replaced with something else,