From 20cba902d8cfda312269db14c85f364c200145d4 Mon Sep 17 00:00:00 2001
From: metagn <metagngn@gmail.com>
Date: Mon, 23 Sep 2024 16:43:04 +0300
Subject: [PATCH] fix `nil` literal giving itself type `untyped`/`typed`

fixes #24164, regression from #20091
---
 compiler/semexprs.nim             | 2 +-
 tests/types/ttopdowninference.nim | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index 41493b04607db..f5b32637e91e3 100644
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -3314,7 +3314,7 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
   of nkNilLit:
     if result.typ == nil:
       result.typ = getNilType(c)
-      if expectedType != nil:
+      if expectedType != nil and expectedType.kind notin {tyUntyped, tyTyped}:
         var m = newCandidate(c, result.typ)
         if typeRel(m, expectedType, result.typ) >= isSubtype:
           result.typ = expectedType
diff --git a/tests/types/ttopdowninference.nim b/tests/types/ttopdowninference.nim
index 2a26e0e34e09d..765761e993ffd 100644
--- a/tests/types/ttopdowninference.nim
+++ b/tests/types/ttopdowninference.nim
@@ -325,3 +325,9 @@ block: # bug #22180
         else:
           (ref A)(nil)
   doAssert y.isNil
+
+block: # issue #24164, related regression
+  proc foo(x: proc ()) = discard
+  template bar(x: untyped = nil) =
+    foo(x)
+  bar()