GHC-7.8 warning on rules that may not fire

Henning Thielemann lemming at
Fri Mar 14 16:57:23 UTC 2014

With GHC-7.8 I get lots of warnings like

src/Foo/Bar.hs:215:6: Warning:
     Rule "foo" may never fire
       because ‘bar’ might inline first
     Probable fix: add an INLINE[n] or NOINLINE[n] pragma on ‘bar’

So far I thought that rewrite RULES always have precedence to INLINE. 
Has this changed? I hesitate to follow the advice of adding phase 
numbers in bracket because I consider these phase numbers a quite 
fragile and non-modular solution (like precedence numbers for infix 

I have found:

Is this still considered for future developments?

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