Validate inferred theta. Fixes #8883

This checks that all the required extensions are enabled for the
inferred type signature.

Updates binary and vector submodules.

5 files changed, 9 insertions, 0 deletions

diff --git a/compiler/llvmGen/LlvmCodeGen.hs b/compiler/llvmGen/LlvmCodeGen.hs
index d0f343fa92..61e7e39a49 100644
--- a/compiler/llvmGen/LlvmCodeGen.hs
+++ b/compiler/llvmGen/LlvmCodeGen.hs
@@ -2,6 +2,7 @@
 -- | This is the top-level module in the LLVM code generator.
 --
 
+{-# LANGUAGE TypeFamilies #-}
 module LlvmCodeGen ( llvmCodeGen, llvmFixupAsm ) where
 
 #include "HsVersions.h"
diff --git a/compiler/nativeGen/RegAlloc/Liveness.hs b/compiler/nativeGen/RegAlloc/Liveness.hs
index 6dd4cec0de..b0e763a6f0 100644
--- a/compiler/nativeGen/RegAlloc/Liveness.hs
+++ b/compiler/nativeGen/RegAlloc/Liveness.hs
@@ -5,6 +5,7 @@
 -- (c) The University of Glasgow 2004-2013
 --
 -----------------------------------------------------------------------------
+{-# LANGUAGE FlexibleContexts, TypeFamilies #-}
 module RegAlloc.Liveness (
         RegSet,
         RegMap, emptyRegMap,
diff --git a/compiler/nativeGen/X86/Instr.hs b/compiler/nativeGen/X86/Instr.hs
index 8284270be1..75e5b9e737 100644
--- a/compiler/nativeGen/X86/Instr.hs
+++ b/compiler/nativeGen/X86/Instr.hs
@@ -9,6 +9,7 @@
 #include "HsVersions.h"
 #include "nativeGen/NCG.h"
 
+{-# LANGUAGE TypeFamilies #-}
 module X86.Instr (Instr(..), Operand(..), PrefetchVariant(..), JumpDest,
                   getJumpDestBlockId, canShortcut, shortcutStatics,
                   shortcutJump, i386_insert_ffrees, allocMoreStack,
diff --git a/compiler/typecheck/TcBinds.lhs b/compiler/typecheck/TcBinds.lhs
index d46e441130..17f124b0d8 100644
--- a/compiler/typecheck/TcBinds.lhs
+++ b/compiler/typecheck/TcBinds.lhs
@@ -54,6 +54,7 @@ import FastString
 import Type(mkStrLitTy)
 import Class(classTyCon)
 import PrelNames(ipClassName)
+import TcValidity (checkValidTheta)
 
 import Control.Monad
 
@@ -562,6 +563,10 @@ tcPolyInfer rec_tc prag_fn tc_sig_fn mono closed bind_list
                           simplifyInfer closed mono name_taus wanted
 
        ; theta <- zonkTcThetaType (map evVarPred givens)
+       -- We need to check inferred theta for validity. The reason is that we
+       -- might have inferred theta that requires language extension that is
+       -- not turned on. See #8883. Example can be found in the T8883 testcase.
+       ; checkValidTheta (InfSigCtxt (fst . head $ name_taus)) theta
        ; exports <- checkNoErrs $ mapM (mkExport prag_fn qtvs theta) mono_infos
 
        ; loc <- getSrcSpanM
diff --git a/compiler/typecheck/TcSMonad.lhs b/compiler/typecheck/TcSMonad.lhs
index b7faf153ca..51f4945564 100644
--- a/compiler/typecheck/TcSMonad.lhs
+++ b/compiler/typecheck/TcSMonad.lhs
@@ -1,5 +1,6 @@
 \begin{code}
 -- Type definitions for the constraint solver
+{-# LANGUAGE TypeFamilies #-}
 module TcSMonad (
 
        -- Canonical constraints, definition is now in TcRnTypes