[GHC] #10637: Cannot suppress "Warning: {-# SOURCE #-} unnecessary in import of ‘A’"

[GHC]

#10637: Cannot suppress "Warning: {-# SOURCE #-} unnecessary in import of  ‘A’"
-----------------------------------------+---------------------------------
              Reporter:  phischu         |             Owner:
                  Type:  bug             |            Status:  new
              Priority:  normal          |         Milestone:
             Component:  Compiler        |           Version:  7.10.1
              Keywords:                  |  Operating System:  Linux
          Architecture:  x86_64 (amd64)  |   Type of failure:  None/Unknown
             Test Case:                  |        Blocked By:
              Blocking:                  |   Related Tickets:
Differential Revisions:                  |
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 Consider the following three files:
 {{{#!hs
 -- A.hs
 module A where
 }}}
 {{{#!hs
 -- A.hs-boot
 module A where
 }}}
 {{{#!hs
 -- B.hs
 module B where

 import {-# SOURCE #-} A
 }}}
 When compiling these three files GHC emits a warning and rightly so:
 {{{
 >ghc B.hs

 B.hs:3:23: Warning: {-# SOURCE #-} unnecessary in import of  ‘A’
 [1 of 3] Compiling A[boot]          ( A.hs-boot, A.o-boot )
 [2 of 3] Compiling A                ( A.hs, A.o )
 [3 of 3] Compiling B                ( B.hs, B.o )
 }}}

 When on the other hand compiling with `-w` I expect the warning to go away
 but it doesn't.
 {{{
 >ghc -w B.hs

 B.hs:3:23: Warning: {-# SOURCE #-} unnecessary in import of  ‘A’
 [1 of 3] Compiling A[boot]          ( A.hs-boot, A.o-boot )
 [2 of 3] Compiling A                ( A.hs, A.o )
 [3 of 3] Compiling B                ( B.hs, B.o )
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10637>
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