diff options
| -rw-r--r-- | compiler/typecheck/TcUnify.lhs | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/compiler/typecheck/TcUnify.lhs b/compiler/typecheck/TcUnify.lhs index e8365db1c7..4aa9b3d3c4 100644 --- a/compiler/typecheck/TcUnify.lhs +++ b/compiler/typecheck/TcUnify.lhs @@ -1488,17 +1488,17 @@ uMetaVar outer swapped tv1 BoxTv ref1 ps_ty2 non_var_ty2 -- -- It should not be the case that tv1 occurs in ty2 -- (i.e. no occurs check should be needed), but if perchance - -- it does, the unbox operation will fill it, and the DEBUG + -- it does, the unbox operation will fill it, and the debug code -- checks for that. - do { final_ty <- unBox ps_ty2 -#ifdef DEBUG - ; meta_details <- readMutVar ref1 - ; case meta_details of - Indirect ty -> WARN( True, ppr tv1 <+> ppr ty ) - return () -- This really should *not* happen - Flexi -> return () -#endif - ; checkUpdateMeta swapped tv1 ref1 final_ty + do { final_ty <- unBox ps_ty2 + ; when debugIsOn $ do + { meta_details <- readMutVar ref1 + ; case meta_details of + Indirect ty -> WARN( True, ppr tv1 <+> ppr ty ) + return () -- This really should *not* happen + Flexi -> return () + } + ; checkUpdateMeta swapped tv1 ref1 final_ty ; return IdCo } |