No non-exhaustive pattern match warning given for empty case analysis

I would expect GHC to warn of a non-exhaustive pattern match at compile-time when faced with this,

{-# LANGUAGE EmptyCase #-}
module Test where

test :: Bool -> Int
test a = case a of

Yet it happily accepts this without complaint. If one attempts to evaluate, e.g., test True the expected "Non-exhaustive patterns in case" error is thrown at runtime.

Trac metadata

Trac field	Value
Version	7.10.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
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CC	edsko
Operating system
Architecture