From b88d181906270a6738f1dafcffc8ec24648b8e8b Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Sat, 4 Apr 2026 14:38:14 -0400
Subject: [PATCH] refactor: make AGCObject.shallow_copy() non-const

prep for moving to ACollector interface
---
 idl/GCObject.json5                      | 8 ++++----
 include/xo/alloc2/gc/AGCObject.hpp      | 4 ++--
 include/xo/alloc2/gc/IGCObject_Any.hpp  | 2 +-
 include/xo/alloc2/gc/IGCObject_Xfer.hpp | 6 +++---
 include/xo/alloc2/gc/RGCObject.hpp      | 6 +++---
 src/alloc2/IGCObject_Any.cpp            | 6 ++++++
 6 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/idl/GCObject.json5 b/idl/GCObject.json5
index 0bbb170d..cbc2ab7e 100644
--- a/idl/GCObject.json5
+++ b/idl/GCObject.json5
@@ -54,7 +54,9 @@
             noexcept: true,
             attributes: [],
         },
-        // Opaque shallow_copy(obj<AAllocator>>) const noexcept
+    ],
+    nonconst_methods: [
+        // Opaque shallow_copy(obj<AAllocator>>) noexcept
         {
             name: "shallow_copy",
             doc: ["copy instance using allocator"],
@@ -66,9 +68,7 @@
             noexcept: true,
             attributes: [],
         },
-    ],
-    nonconst_methods: [
-        // size_type forward_children(obj<ACollector>) const noexcept
+        // size_type forward_children(obj<ACollector>) noexcept
         {
             name: "forward_children",
             doc: ["during GC: forward immdiate children"],
diff --git a/include/xo/alloc2/gc/AGCObject.hpp b/include/xo/alloc2/gc/AGCObject.hpp
index 1037f253..e9a4e519 100644
--- a/include/xo/alloc2/gc/AGCObject.hpp
+++ b/include/xo/alloc2/gc/AGCObject.hpp
@@ -64,10 +64,10 @@ public:
     virtual void _drop(Opaque d) const noexcept = 0;
     /** memory consumption for this instance **/
     virtual size_type shallow_size(Copaque data)  const  noexcept = 0;
-    /** copy instance using allocator **/
-    virtual Opaque shallow_copy(Copaque data, obj<AAllocator> mm)  const  noexcept = 0;
 
     // nonconst methods
+    /** copy instance using allocator **/
+    virtual Opaque shallow_copy(Opaque data, obj<AAllocator> mm)  const  noexcept = 0;
     /** during GC: forward immdiate children **/
     virtual size_type forward_children(Opaque data, obj<ACollector> gc)  const  noexcept = 0;
     ///@}
diff --git a/include/xo/alloc2/gc/IGCObject_Any.hpp b/include/xo/alloc2/gc/IGCObject_Any.hpp
index 9ff7bb2e..2658c599 100644
--- a/include/xo/alloc2/gc/IGCObject_Any.hpp
+++ b/include/xo/alloc2/gc/IGCObject_Any.hpp
@@ -62,9 +62,9 @@ namespace mm {
 
         // const methods
         [[noreturn]] size_type shallow_size(Copaque)  const  noexcept override { _fatal(); }
-        [[noreturn]] Opaque shallow_copy(Copaque, obj<AAllocator>)  const  noexcept override { _fatal(); }
 
         // nonconst methods
+        [[noreturn]] Opaque shallow_copy(Opaque, obj<AAllocator>)  const  noexcept override;
         [[noreturn]] size_type forward_children(Opaque, obj<ACollector>)  const  noexcept override;
 
         ///@}
diff --git a/include/xo/alloc2/gc/IGCObject_Xfer.hpp b/include/xo/alloc2/gc/IGCObject_Xfer.hpp
index 12010edf..e00595e8 100644
--- a/include/xo/alloc2/gc/IGCObject_Xfer.hpp
+++ b/include/xo/alloc2/gc/IGCObject_Xfer.hpp
@@ -52,11 +52,11 @@ namespace mm {
         size_type shallow_size(Copaque data)  const  noexcept override {
             return I::shallow_size(_dcast(data));
         }
-        Opaque shallow_copy(Copaque data, obj<AAllocator> mm)  const  noexcept override {
-            return I::shallow_copy(_dcast(data), mm);
-        }
 
         // non-const methods
+        Opaque shallow_copy(Opaque data, obj<AAllocator> mm)  const  noexcept override {
+            return I::shallow_copy(_dcast(data), mm);
+        }
         size_type forward_children(Opaque data, obj<ACollector> gc)  const  noexcept override {
             return I::forward_children(_dcast(data), gc);
         }
diff --git a/include/xo/alloc2/gc/RGCObject.hpp b/include/xo/alloc2/gc/RGCObject.hpp
index d24994a8..c4a668e6 100644
--- a/include/xo/alloc2/gc/RGCObject.hpp
+++ b/include/xo/alloc2/gc/RGCObject.hpp
@@ -58,11 +58,11 @@ public:
     size_type shallow_size()  const  noexcept {
         return O::iface()->shallow_size(O::data());
     }
-    Opaque shallow_copy(obj<AAllocator> mm)  const  noexcept {
-        return O::iface()->shallow_copy(O::data(), mm);
-    }
 
     // non-const methods (still const in router!)
+    Opaque shallow_copy(obj<AAllocator> mm)  noexcept {
+        return O::iface()->shallow_copy(O::data(), mm);
+    }
     size_type forward_children(obj<ACollector> gc)  noexcept {
         return O::iface()->forward_children(O::data(), gc);
     }
diff --git a/src/alloc2/IGCObject_Any.cpp b/src/alloc2/IGCObject_Any.cpp
index 10ff8f6a..426f68a9 100644
--- a/src/alloc2/IGCObject_Any.cpp
+++ b/src/alloc2/IGCObject_Any.cpp
@@ -35,6 +35,12 @@ IGCObject_Any::_valid
 
 // nonconst methods
 
+auto
+IGCObject_Any::shallow_copy(Opaque, obj<AAllocator>)  const  noexcept -> Opaque
+{
+    _fatal();
+}
+
 auto
 IGCObject_Any::forward_children(Opaque, obj<ACollector>)  const  noexcept -> size_type
 {