From 0aa623fcf7885d1879e88339267275374af3e9e2 Mon Sep 17 00:00:00 2001
From: araq <araq4k@proton.me>
Date: Fri, 29 May 2026 07:50:21 +0200
Subject: [PATCH] fixes #25830

---
 compiler/sigmatch.nim | 6 +++++-
 compiler/types.nim    | 3 ++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index bf9c2d2050..7375a28262 100644
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -791,8 +791,12 @@ proc procParamTypeRel(c: var TCandidate; f, a: PType): TTypeRelation =
     # different C types (size_t vs unsigned long long).
     let fCheck = concreteType(c, f)
     let aCheck = concreteType(c, a)
+    # `tfVarIsPtr` is an internal lowering artifact set during a proc's body
+    # analysis; a `proc` type literal's `var`/`lent` return never carries it,
+    # so `IgnoreFlags` keeps it from blocking matching `var T` against `var T`.
+    # The var/lent consistency itself is handled by `inconsistentVarTypes` below.
     if fCheck != nil and aCheck != nil and
-        not sameBackendTypePickyAliases(fCheck, aCheck):
+        not sameBackendTypePickyAliases(fCheck, aCheck, {IgnoreFlags}):
       result = isNone
 
   if result <= isSubrange or inconsistentVarTypes(f, a):
diff --git a/compiler/types.nim b/compiler/types.nim
index de24471e7d..f4c7e74bc5 100644
--- a/compiler/types.nim
+++ b/compiler/types.nim
@@ -1069,9 +1069,10 @@ proc sameBackendTypeIgnoreRange*(x, y: PType): bool =
   c.cmp = dcEqIgnoreDistinct
   result = sameTypeAux(x, y, c)
 
-proc sameBackendTypePickyAliases*(x, y: PType): bool =
+proc sameBackendTypePickyAliases*(x, y: PType, flags: TTypeCmpFlags = {}): bool =
   var c = initSameTypeClosure()
   c.flags.incl {IgnoreTupleFields, IgnoreRangeShallow, PickyCAliases, PickyBackendAliases}
+  c.flags.incl flags
   c.cmp = dcEqIgnoreDistinct
   result = sameTypeAux(x, y, c)