[GHC] #14089: Segmentation fault/access violation using Yesod and Postgresql

[GHC]

#14089: Segmentation fault/access violation using Yesod and Postgresql
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        Reporter:  Burtannia     |                Owner:  (none)
            Type:  bug           |               Status:  infoneeded
        Priority:  normal        |            Milestone:
       Component:  Compiler      |              Version:  8.0.2
      Resolution:                |             Keywords:
Operating System:  Windows       |         Architecture:  x86_64 (amd64)
 Type of failure:  None/Unknown  |            Test Case:
      Blocked By:                |             Blocking:
 Related Tickets:                |  Differential Rev(s):
       Wiki Page:                |
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Comment (by RyanGlScott):

 Thanks Burtannia. I tried building each of these examples with both GHC
 8.0.2 and 8.2.1. Neither example segfaulted on GHC 8.2.1. On GHC 8.0.2,
 the `postgres` example didn't segfault, but the `sqlite` example did:

 {{{
 $ cabal build
 Preprocessing library for sqliteExample-0.0.0..
 Building library for sqliteExample-0.0.0..
 [ 1 of 11] Compiling Settings         ( src\Settings.hs,
 dist\build\Settings.o )
 [ 2 of 11] Compiling Settings.StaticFiles ( src\Settings\StaticFiles.hs,
 dist\build\Settings\StaticFiles.o )
 [ 3 of 11] Compiling Model            ( src\Model.hs, dist\build\Model.o )
 [ 4 of 11] Compiling Import.NoFoundation ( src\Import\NoFoundation.hs,
 dist\build\Import\NoFoundation.o )
 [ 5 of 11] Compiling Foundation       ( src\Foundation.hs,
 dist\build\Foundation.o )
 Segmentation fault/access violation in generated code
 }}}

 Running `cabal build` after this causes the build to succeed. However,
 `cabal clean`-ing and re-running `cabal build` causes the segfault to
 resurface:

 {{{
 $ cabal build
 Preprocessing library for sqliteExample-0.0.0..
 Building library for sqliteExample-0.0.0..
 [ 1 of 11] Compiling Settings         ( src\Settings.hs,
 dist\build\Settings.o )
 [ 2 of 11] Compiling Settings.StaticFiles ( src\Settings\StaticFiles.hs,
 dist\build\Settings\StaticFiles.o )
 Segmentation fault/access violation in generated code
 }}}

 Notice that it appeared to segfault in a different location that time!
 Moreover, you appear to need to build these modules in parallel (`cabal
 build`'s default behavior) to trigger the segfault (at least, on my 64-bit
 Windows 10 machine), since I can't get it to segfault with `cabal build
 -j1`.

 My initial hunch is that this is an occurrence of #13112, since both
 `Foundation` and `Settings.StaticFiles` use quite a bit of Template
 Haskell.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14089#comment:8>
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