diff --git a/ShellCheck/Analytics.hs b/ShellCheck/Analytics.hs
index 9962b4eab15dcbdf764721a749b2992f29a84b4c..9649a90c4dbca82f623cef39145389dccb0679f0 100644
--- a/ShellCheck/Analytics.hs
+++ b/ShellCheck/Analytics.hs
@@ -264,7 +264,8 @@ checkDivBeforeMult _ = return ()
 prop_checkArithmeticDeref = verify checkArithmeticDeref "echo $((3+$foo))"
 prop_checkArithmeticDeref2 = verify checkArithmeticDeref "cow=14; (( s+= $cow ))"
 prop_checkArithmeticDeref3 = verifyNot checkArithmeticDeref "cow=1/40; (( s+= ${cow%%/*} ))"
-checkArithmeticDeref (TA_Expansion _ (T_DollarBraced id str)) | not $ any (`elem` "/.:#%") $ str =
+prop_checkArithmeticDeref4 = verifyNot checkArithmeticDeref "(( ! $? ))"
+checkArithmeticDeref (TA_Expansion _ (T_DollarBraced id str)) | not $ any (`elem` "/.:#%?*@") $ str =
     warn id $ "Don't use $ on variables in (( )) unless you want to dereference twice"
 checkArithmeticDeref _ = return ()
 
diff --git a/ShellCheck/Parser.hs b/ShellCheck/Parser.hs
index b91442bb30440d58fc2e4ee362a74506dc5d8472..64a158f4ef039373e8c213ba1941b885566b4826 100644
--- a/ShellCheck/Parser.hs
+++ b/ShellCheck/Parser.hs
@@ -279,6 +279,7 @@ prop_a6 = isOk readArithmeticContents " 1 | 2 ||3|4"
 prop_a7 = isOk readArithmeticContents "3*2**10"
 prop_a8 = isOk readArithmeticContents "3"
 prop_a9 = isOk readArithmeticContents "a^!-b"
+prop_aA = isOk readArithmeticContents "! $?"
 readArithmeticContents =
     readSequence
   where
@@ -359,6 +360,7 @@ readArithmeticContents =
     readNegated = do
         id <- getNextId
         op <- oneOf "!~"
+        spacing
         x <- readAnySigned
         return $ TA_Unary id [op] x