Fix the GHC 7.10 build
authorRyan Scott <ryan.gl.scott@gmail.com>
Thu, 19 Jan 2017 19:43:25 +0000 (14:43 -0500)
committerRyan Scott <ryan.gl.scott@gmail.com>
Thu, 19 Jan 2017 19:43:28 +0000 (14:43 -0500)
commitf5bea9820eb5d573718d9a5e82c3f5acd7dbb734
tree633a2737c05a6227465605acca20cdca7180eb1d
parente7985ed23ddc68b6a2e4af753578dc1d9e8ab4c9
Fix the GHC 7.10 build

Following e7985ed23ddc68b6a2e4af753578dc1d9e8ab4c9. HasDebugCallStack now
appears in IdInfo, which requires `FlexibleContexts` to be enabled when built
with GHC 7.10.
compiler/basicTypes/IdInfo.hs