Fixes #25330 (#25336)

Fixed state optimizer. It did not replace deleted states in
`excLandingState`.

compiler/closureiters.nim

@@ -1307,16 +1307,15 @@ proc countStateOccurences(ctx: var Ctx, n: PNode, stateOccurences: var openArray
 
 proc replaceDeletedStates(ctx: var Ctx, n: PNode): PNode =
   result = n
-  for i in 0 ..< n.safeLen:
-    let c = n[i]
-    if c.kind == nkIntLit:
-      let idx = c.intVal
-      if idx >= 0 and idx < ctx.states.len and ctx.states[idx].label == c and ctx.states[idx].deletable:
-        let gt = ctx.replaceDeletedStates(skipStmtList(ctx.states[idx].body))
-        assert(gt.kind == nkGotoState)
-        n[i] = gt[0]
-    else:
-      n[i] = ctx.replaceDeletedStates(c)
+  if n.kind == nkIntLit:
+    let idx = n.intVal
+    if idx >= 0 and idx < ctx.states.len and ctx.states[idx].label == n and ctx.states[idx].deletable:
+      let gt = ctx.replaceDeletedStates(skipStmtList(ctx.states[idx].body))
+      assert(gt.kind == nkGotoState)
+      result = gt[0]
+  else:
+    for i in 0 ..< n.safeLen:
+      n[i] = ctx.replaceDeletedStates(n[i])
 
 proc replaceInlinedStates(ctx: var Ctx, n: PNode): PNode =
   ## Find all nkGotoState(stateIdx) nodes that do not follow nkYield.
@@ -1347,6 +1346,7 @@ proc optimizeStates(ctx: var Ctx) =
   # Replace deletable state labels to labels of respective non-empty states
   for i in 0 .. ctx.states.high:
     ctx.states[i].body = ctx.replaceDeletedStates(ctx.states[i].body)
+    ctx.states[i].excLandingState = ctx.replaceDeletedStates(ctx.states[i].excLandingState)
 
   # Remove deletable states
   var i = 0

tests/iter/tyieldintry.nim

@@ -17,9 +17,12 @@ proc testClosureIterAux(it: iterator(): int, exceptionExpected: bool, expectedRe
 
   var exceptionCaught = false
 
+  var maxIterations = 10000
   try:
     for i in it():
       closureIterResult.add(i)
+      dec maxIterations
+      doAssert(maxIterations > 0, "Too many iterations in test. Infinite loop?")
   except TestError:
     exceptionCaught = true
 
@@ -847,3 +850,50 @@ block:
     doAssert(w() == 123)
     doAssert(getCurrentExceptionMsg() == "Outer error")
   doAssert(getCurrentExceptionMsg() == "")
+
+block: #25330 (v1)
+  iterator count1(): int {.closure.} =
+    yield 1
+    raiseTestError()
+
+  iterator count0(): int {.closure.} =
+    try:
+      var count = count1
+      while true:
+        yield count()
+        if finished(count): break
+    finally:
+      try:
+        checkpoint(2)
+        var count2 = count1
+        while true:
+          yield count2()
+          if finished(count2): break
+        discard  # removing this outputs "raise"
+      except:
+        checkpoint(3)
+        raise
+
+  testExc(count0, 1, 2, 1, 3)
+
+block: #25330 (v2)
+  iterator count1(): int {.closure.} =
+    yield 1
+    raiseTestError()
+
+  iterator count0(): int {.closure.} =
+    try:
+      var count = count1
+      for x in 0 .. 10:
+        yield count()
+    finally:
+      try:
+        checkpoint(2)
+        var count2 = count1
+        for x in 0 .. 10:
+          yield count2()
+      except:
+        checkpoint(3)
+        raise
+
+  testExc(count0, 1, 2, 1, 3)