Misleading error message on mising BangPatterns extension

For following program I'm getting an unexpected error message.

foo :: Int -> Int
foo = bar
  where
    bar :: Int -> Int
    bar !i = i

$ ghc -o Test Test.hs
[1 of 1] Compiling Main             ( Test.hs, Test.o )

Test.hs:4:5: error:
    The type signature for ‘bar’ lacks an accompanying binding
  |
4 |     bar :: Int -> Int
  |     ^^^

Enabling -XBangPatterns fixes the issue but I wanted the compiler to suggest me to enable it:

$ ghc -XBangPatterns -o Test Test.hs
[1 of 1] Compiling Main             ( Test.hs, Test.o )

Test.hs:1:1: error:
    The IO action ‘main’ is not defined in module ‘Main’
  |
1 | foo :: Int -> Int
  | ^

Trac metadata

Trac field	Value
Version	8.4.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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