Merge remote-tracking branch 'origin/devel' into pr_so_so

compiler/lambdalifting.nim

@@ -408,6 +408,12 @@ Consider:
 proc isTypeOf(n: PNode): bool =
   n.kind == nkSym and n.sym.magic in {mTypeOf, mType}
 
+proc isEnvTypeForRoutine(envTyp: PType; routine: PSym): bool =
+  ## True if `envTyp` is (maybe wrapped) env object type owned by `routine`, as
+  ## created by `getEnvTypeForOwner` / `createEnvObj`.
+  let obj = envTyp.skipTypes({tyOwned, tyRef, tyPtr})
+  result = obj.kind == tyObject and obj.owner.id == routine.id
+
 proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
   var cp = getEnvParam(fn)
   let owner = if fn.kind == skIterator: fn else: fn.skipGenericOwner
@@ -418,7 +424,13 @@ proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
     cp.typ = t
     addHiddenParam(fn, cp)
   elif cp.typ != t and fn.kind != skIterator:
-    localError(c.graph.config, fn.info, "internal error: inconsistent environment type")
+    # Nested `liftLambdas` uses a fresh `DetectionPass`, so `getEnvTypeForOwner`
+    # can allocate another PType for the same logical env; the hidden param from
+    # the inner pass is authoritative (bug #21242).
+    if isEnvTypeForRoutine(cp.typ, owner) and isEnvTypeForRoutine(t, owner):
+      c.ownerToType[owner.id] = cp.typ
+    else:
+      localError(c.graph.config, fn.info, "internal error: inconsistent environment type")
   #echo "adding closure to ", fn.name.s
 
 proc iterEnvHasUpField(g: ModuleGraph, iter: PSym): bool =

compiler/semstmts.nim

@@ -1101,7 +1101,7 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
       iterBase.skipModifier
     else:
       skipTypes(iterBase, {tyAlias, tySink, tyOwned})
-  var iter = iterType
+  var iter = skipTypes(iterType, {tyGenericInst})
   var iterAfterVarLent = iter.skipTypes({tyGenericInst, tyAlias, tyLent, tyVar})
   # n.len == 3 means that there is one for loop variable
   # and thus no tuple unpacking:

tests/iter/t21242_nested_closure_in_iter.nim

@@ -0,0 +1,23 @@
+# Regression test for bug #21242
+discard """
+  action: compile
+"""
+
+iterator iterSome(): int =
+  proc inner1() =
+    let something = 6
+    proc inner2() =
+      let othersomething = something
+    inner2()
+
+  for n in 0 .. 10:
+    inner1()
+    yield n
+
+proc test() =
+  proc test1() =
+    for v in iterSome():
+      discard
+  test1()
+
+test()

tests/iter/t25704.nim

@@ -0,0 +1,13 @@
+import std/[sugar, strutils]
+
+type Res[T] = tuple[a: int, b: string]
+iterator test(): Res[string] =
+  yield (1, "")
+
+for (i, s) in test():
+  static:
+    echo typeof(i)
+    echo typeof(s)
+  let
+    a: int = i
+    b: string = s