fix pair compiler warnings

src/Language/GLSL.hs

@@ -176,8 +176,6 @@ type CheckResult = Either CheckFailure CheckSuccess
 type CheckSuccess = (Program, [Warn])
 type CheckFailure = (Error, [Warn])
 
-type LineNumber = Int
-
 data Error
   = ErrUnimplementedCheckProgram
   | ErrVariableDeclaredMultipleTimes Variables
@@ -268,6 +266,6 @@ counts' (x:xs) cts =
         [(a, ct + 1) | (a, ct) <- cts
                      , a == x
         ] ++
-        [t | t@(a, ct) <- cts
+        [t | t@(a, _) <- cts
            , a /= x
         ]