fix build and tests for ghc >8.6

src/Language/Wasm/Binary.hs

@@ -154,7 +154,7 @@ getName = do
 putResultType :: ResultType -> Put
 putResultType [] = putWord8 0x40
 putResultType [valType] = put valType
-putResultType _ = fail "Current WebAssembly spec does not support returning more then one value"
+putResultType _ = error "Current WebAssembly spec does not support returning more then one value"
 
 getResultType :: Get ResultType
 getResultType = do

src/Language/Wasm/Interpreter.hs

@@ -903,11 +903,11 @@ eval budget store FunctionInstance { funcType, moduleInstance, code = Function {
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IXor) =
             return $ Done ctx { stack = VI64 (v1 `xor` v2) : rest }
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IShl) =
-            return $ Done ctx { stack = VI64 (v1 `shiftL` (fromIntegral v2 `rem` 64)) : rest }
+            return $ Done ctx { stack = VI64 (v1 `shiftL` (fromIntegral (v2 `rem` 64))) : rest }
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IShrU) =
-            return $ Done ctx { stack = VI64 (v1 `shiftR` (fromIntegral v2 `rem` 64)) : rest }
+            return $ Done ctx { stack = VI64 (v1 `shiftR` (fromIntegral (v2 `rem` 64))) : rest }
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IShrS) =
-            return $ Done ctx { stack = VI64 (asWord64 $ asInt64 v1 `shiftR` (fromIntegral v2 `rem` 64)) : rest }
+            return $ Done ctx { stack = VI64 (asWord64 $ asInt64 v1 `shiftR` (fromIntegral (v2 `rem` 64))) : rest }
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IRotl) =
             return $ Done ctx { stack = VI64 (v1 `rotateL` fromIntegral v2) : rest }
         step ctx@EvalCtx{ stack = (VI64 v2:VI64 v1:rest) } (IBinOp BS64 IRotr) =

src/Language/Wasm/Script.hs

@@ -194,12 +194,12 @@ runScript onAssertFail script = do
         runAssert st assert@(AssertInvalid moduleDef failureString) =
             let (_, m) = buildModule moduleDef in
             case Validate.validate m of
-                Right _ -> onAssertFail "Invalid module pass validation" assert
+                Right _ -> onAssertFail "An invalid module passed validation step" assert
                 Left reason ->
                     if failureString `elem` getFailureString reason
                     then return ()
                     else
-                        let msg = "Module invalid for other reason. Expected "
+                        let msg = "Module is invalid for other reason. Expected "
                                 ++ show failureString
                                 ++ ", but actual is "
                                 ++ show (getFailureString reason)

src/Language/Wasm/Validate.hs

@@ -16,8 +16,8 @@ import qualified Data.Set as Set
 import Data.List (foldl')
 import qualified Data.Text.Lazy as TL
 import Data.Maybe (fromMaybe, maybeToList, catMaybes)
-import Data.Monoid ((<>))
 import Numeric.Natural (Natural)
+import Prelude hiding ((<>))
 
 import Control.Monad (foldM)
 import Control.Monad.Reader (ReaderT, runReaderT, withReaderT, ask)
@@ -52,6 +52,10 @@ data ValidationError =
 
 type ValidationResult = Either ValidationError ()
 
+-- semigroup definition for Either a b is in conflict with my ad-hoc instance
+-- to keep an old code Prelude version is hidden and redefined locally
+(<>) = mappend
+
 instance Monoid ValidationResult where
     mempty = Right ()
     mappend (Right ()) vr = vr