fixes #2007

compiler/lambdalifting.nim

@@ -162,9 +162,9 @@ proc addHiddenParam(routine: PSym, param: PSym) =
   # some nkEffect node:
   param.position = routine.typ.n.len-1
   addSon(params, newSymNode(param))
-  incl(routine.typ.flags, tfCapturesEnv)
+  #incl(routine.typ.flags, tfCapturesEnv)
   assert sfFromGeneric in param.flags
-  #echo "produced environment: ", param.id, " for ", routine.name.s
+  #echo "produced environment: ", param.id, " for ", routine.id
 
 proc getHiddenParam(routine: PSym): PSym =
   let params = routine.ast.sons[paramsPos]

compiler/semstmts.nim

@@ -958,15 +958,17 @@ proc semInferredLambda(c: PContext, pt: TIdTable, n: PNode): PNode =
   var n = n
 
   let original = n.sons[namePos].sym
-  let s = copySym(original, false)
-  incl(s.flags, sfFromGeneric)
+  let s = original #copySym(original, false)
+  #incl(s.flags, sfFromGeneric)
+  #s.owner = original
 
   n = replaceTypesInBody(c, pt, n, original)
   result = n
   s.ast = result
   n.sons[namePos].sym = s
   n.sons[genericParamsPos] = emptyNode
-  let params = n.typ.n
+  # for LL we need to avoid wrong aliasing
+  let params = copyTree n.typ.n
   n.sons[paramsPos] = params
   s.typ = n.typ
   for i in 1..<params.len:
@@ -974,6 +976,7 @@ proc semInferredLambda(c: PContext, pt: TIdTable, n: PNode): PNode =
                               tyFromExpr, tyFieldAccessor}+tyTypeClasses:
       localError(params[i].info, "cannot infer type of parameter: " &
                  params[i].sym.name.s)
+    #params[i].sym.owner = s
   openScope(c)
   pushOwner(s)
   addParams(c, params, skProc)

tests/async/tlambda.nim

@@ -0,0 +1,55 @@
+
+# bug 2007
+
+import asyncdispatch, asyncnet, logging, json, uri, strutils, future
+
+type
+  Builder = ref object
+    client: Client
+    build: Build
+
+  ProgressCB* = proc (message: string): Future[void] {.closure, gcsafe.}
+
+  Build* = ref object
+    onProgress*: ProgressCB
+
+  Client = ref ClientObj
+  ClientObj = object
+    onMessage: proc (client: Client, msg: JsonNode): Future[void]
+
+proc newClient*(name: string,
+                onMessage: (Client, JsonNode) -> Future[void]): Client =
+  new result
+  result.onMessage = onMessage
+
+proc newBuild*(onProgress: ProgressCB): Build =
+  new result
+  result.onProgress = onProgress
+
+proc start(build: Build, repo, hash: string) {.async.} =
+  let path = repo.parseUri().path.toLower()
+
+proc onProgress(builder: Builder, message: string) {.async.} =
+  debug($message)
+
+proc onMessage(builder: Builder, message: JsonNode) {.async.} =
+  debug("onMessage")
+
+proc newBuilder(): Builder =
+  var cres: Builder
+  new cres
+
+  cres.client = newClient("builder", (client, msg) => (onMessage(cres, msg)))
+  cres.build = newBuild(
+      proc (msg: string): Future[void] {.closure, gcsafe.} = onProgress(cres, msg))
+  return cres
+
+proc main() =
+  # Set up logging.
+  var console = newConsoleLogger(fmtStr = verboseFmtStr)
+  addHandler(console)
+
+  var builder = newBuilder()
+
+
+main()