From e58acc2e1e98f62637c47769e6a31cea1c392b9d Mon Sep 17 00:00:00 2001
From: ringabout <43030857+ringabout@users.noreply.github.com>
Date: Mon, 23 Feb 2026 20:40:31 +0800
Subject: [PATCH] fixes #25005; new doesn't work with ref object (#25532)

fixes #25005

In `semTypeIdent`, when resolving a typedesc parameter inside a generic
instantiation, the code took a shortcut: it returned the symbol of the
element type (`bound = result.typ.elementType.sym`). However, for
generic types like `RpcResponse[T] = ref object`, the instantiated
object type (e.g., `RpcResponse:ObjectType[string]`) is a copy with a
new type ID but still points to the same symbol as the uninstantiated
generic body type. That symbol's .typ refers to the original
uninstantiated type, which still contains unresolved generic params `T`
---
 compiler/semtypes.nim               |  4 +++-
 tests/generics/tgenerics_issues.nim | 12 ++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index c6ed5e77dc..1a4bd24965 100644
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -2049,7 +2049,9 @@ proc semTypeIdent(c: PContext, n: PNode): PSym =
         # proc signature for example
         if c.inGenericInst > 0:
           let bound = result.typ.elementType.sym
-          if bound != nil: return bound
+          # the symbol may still point to the uninstantiated generic body type 
+          if bound != nil and bound.typ == result.typ.elementType:
+            return bound
           return result
         if result.typ.sym == nil:
           localError(c.config, n.info, errTypeExpected)
diff --git a/tests/generics/tgenerics_issues.nim b/tests/generics/tgenerics_issues.nim
index da202874e1..e865c8f7be 100644
--- a/tests/generics/tgenerics_issues.nim
+++ b/tests/generics/tgenerics_issues.nim
@@ -902,3 +902,15 @@ block: # issue #25494
       a, b, c
 
   foo[MyEnum]()
+
+block: # issue #25005
+  type
+    RpcResponse[T] = ref object
+      result: T
+
+  func testit[T](p: var ref T) =
+    p = new(T)
+
+  var v: RpcResponse[string]
+  testit(v)
+