-"tcfail051.hs", line 3: undefined class: B
-
-"tcfail051.hs", line 3: "op1" is not an operation of class "*UNBOUND*B".
-Fail: Compilation errors found
+tcfail051.hs:4:
+ Type constructor or class not in scope: `B'
+
-ghc: execution of the Haskell compiler had trouble
+Compilation had errors