I tried to land bug 856358 and discovered that renaming an IDL file requires a clobber. This shouldn't be necessary.

I don't suppose you know why this requires a clobber, do you? If it's in IDL building itself, it should get fixed by bug 850380. If it's in some downstream system, we might be hosed until more things are more intelligent.

All I know is that renaming dom/interfaces/contacts/nsIDOMContactProperties.idl to nsIContactProperties.idl caused this failure: make[6]: *** No rule to make target `/builds/slave/m-in-osx64_g-00000000000000000/build/dom/interfaces/contacts/nsIDOMContactProperties.idl', needed by `_xpidlgen/nsIDOMContactManager.xpt'. Stop. make[6]: *** Waiting for unfinished jobs....

Well, that's interesting. I would think the missing .idl would have been removed by mddepend.pl. This is most weird. I'm optimistic this will go away in bug 850380. Let's leave open to track just in case.

I think this is just fallout from bug 462463: http://mxr.mozilla.org/mozilla-central/source/config/rules.mk#1357 http://mxr.mozilla.org/mozilla-central/source/xpcom/idl-parser/typelib.py#296 The patch there didn't change typelib.py to write out extra dep lines for the input IDL files, and we're not running mddepend.pl anymore which used to fix that.