From 8b8c3ea0c07d05ae41cd88540d8b66a440233f3c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20Kozak?= <bartlomiejkozak@proton.me>
Date: Fri, 27 Mar 2026 12:18:44 +0100
Subject: [PATCH] fix: 24765 SAM conversion fails with "cannot override an
 extension method" for Self-based type classes

---
 compiler/src/dotty/tools/dotc/ast/tpd.scala |  4 ++--
 tests/pos/i24765.scala                      | 12 ++++++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)
 create mode 100644 tests/pos/i24765.scala

diff --git a/compiler/src/dotty/tools/dotc/ast/tpd.scala b/compiler/src/dotty/tools/dotc/ast/tpd.scala
index b7827724bd7e..27f2cd349976 100644
--- a/compiler/src/dotty/tools/dotc/ast/tpd.scala
+++ b/compiler/src/dotty/tools/dotc/ast/tpd.scala
@@ -398,8 +398,8 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
           if !overridden.is(Deferred) then fwdMeth.setFlag(Override)
         DefDef(fwdMeth, ref(fn).appliedToArgss(_))
       }
-      termForwarders.map((name, sym) => forwarder(name, sym)) ++
-      typeMembers.map((name, info) => TypeDef(newSymbol(cls, name, Synthetic, info).entered))
+      val typeDefs = typeMembers.map((name, info) => TypeDef(newSymbol(cls, name, Synthetic, info).entered))
+      termForwarders.map((name, sym) => forwarder(name, sym)) ++ typeDefs
     }
   }
 
diff --git a/tests/pos/i24765.scala b/tests/pos/i24765.scala
new file mode 100644
index 000000000000..78c67123fc0f
--- /dev/null
+++ b/tests/pos/i24765.scala
@@ -0,0 +1,12 @@
+import language.experimental.modularity
+
+trait A[T]:
+  extension(t: T) def foo: T
+
+trait B:
+  type Self
+  extension(t: Self) def foo: Self
+
+given A[Int] = x => x // ok before
+
+given Int is B = x => x // was: "cannot override an extension method"