Location info for error message with multiple source locations

Currently:

MonadFailErrors.hs:16:5: error:
    • Could not deduce (MonadFail m)
        arising from a do statement
        with the failable pattern ‘Just x’
      from the context: Monad m
        bound by the type signature for:
                   general :: Monad m => m a
at MonadFailErrors.hs:14:1-25

better:

MonadFailErrors.hs:16:5: error:
    • Could not deduce (MonadFail m)
        arising from a do statement
        with the failable pattern ‘Just x’
      from the context: Monad m
        bound by the type signature for:
                   general :: Monad m => m a
MonadFailErrors.hs:14:1-25: defined here 

Rationale:

Code editors (Emacs) react to file paths and line numbers in the first column and provide affordances, like go to file after clicking.

Related work:

Similar mechanism is used by VisualStudio C compiler, gcc, clang. All location information is put in front, so that jump to source code works reliably.

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
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