[GHC] #10506: SourceNotes are not applied to all identifiers

10 Jun 2015

      #10506: SourceNotes are not applied to all identifiers
-------------------------------------+-------------------------------------
              Reporter:  gridaphobe  |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:  7.10.2
             Component:  Compiler    |           Version:  7.10.1
              Keywords:              |  Operating System:  Unknown/Multiple
          Architecture:              |   Type of failure:  None/Unknown
  Unknown/Multiple                   |        Blocked By:
             Test Case:              |   Related Tickets:
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
 Compiling

 {{{
 module Foo where

 foo x = x + 1

 bar y = foo y
 }}}

 with `-g` produces

 {{{
 $ ghc -g -ddump-ticked test.hs
 [1 of 1] Compiling Foo              ( test.hs, test.o )
 AbsBinds [a_avC] [$dNum_avD]
   {Exports: [foo <= foo_amB
                <>]
    Exported types: foo :: forall a_avC. Num a_avC => a_avC -> a_avC
                    [LclId, Str=DmdType]
    Binds: -- ticks = [srctest.hs:3:1-13]
           foo_amB x_alA
             = srctest.hs:3:9-13 (+)
                                     srctest.hs:3:9 x_alA
 srctest.hs:3:13 1}
 AbsBinds [a_avV] [$dNum_avW]
   {Exports: [bar <= bar_avN
                <>]
    Exported types: bar :: forall a_avV. Num a_avV => a_avV -> a_avV
                    [LclId, Str=DmdType]
    Binds: -- ticks = [srctest.hs:5:1-13]
           bar_avN y_amz = srctest.hs:5:9-13 foo (srctest.hs:5:13
 y_amz)}
 }}}

 Note that neither the occurrence of `(+)` in `foo`, nor the occurrence of
 `foo` in `bar` have their own Ticks. Instead they are only covered by the
 Tick for the entire application `x + 1` (resp. `foo y`).

 I'm trying to use the new SourceNote infrastructure to map CoreExprs back
 to their original source location, but unfortunately I need these
 locations for each identifier in the source.

 Would it be reasonable to add a SourceNote to each occurrence of an
 identifier?

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10506
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