diff options
| -rw-r--r-- | compiler/GHC/IfaceToCore.hs | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/compiler/GHC/IfaceToCore.hs b/compiler/GHC/IfaceToCore.hs index bf40b2947c..e72c931ae6 100644 --- a/compiler/GHC/IfaceToCore.hs +++ b/compiler/GHC/IfaceToCore.hs @@ -1302,11 +1302,10 @@ tcIfaceCompleteMatch (IfaceCompleteMatch ms mtc) = forkM doc $ do -- See Note [P ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ We need to be lazy when type checking the interface, since these functions are called when the interface itself is being loaded, which means it is not in the -PIT yet. If we are not lazy enough, in certain cases we might recursively try to -load the same interface in an infinite loop. - -For this reason, the forkM should be around as much of the computation as -possible. +PIT yet. In particular, the `tcIfaceTCon` must be inside the forkM, otherwise +we'll try to look it up the TyCon, find it's not there, and so initiate the +process (again) of loading the (very same) interface file. Result: infinite +loop. See #19744. -} {- |