Consider the scenario 1. A user compiles a module with and without -dynamic to create `.hi` and `.dyn_hi` files. They use different options for each (ones which affect the recompilation checker). 2. They then try to recompile using `--make` mode. 3. We should recompile because `.hi` and `.dyn_hi` do not match (they were compiled with different flags) At the moment we will not recompile because the flags hash is not included in the interface hash. There is already a similar test for this `dynamicToo001MakeB`, but it changes the source file rather than any options. Root cause: The flags hash is not included in the interface hash.