From 6dd635599ce9460d7dc6f80d054a9cf71bebade5 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Fri, 27 Feb 2026 13:04:46 +1100
Subject: [PATCH] nix-build: + xo-object2 builds

---
 default.nix                              |  2 +
 pkgs/xo-object2.nix                      | 48 ++++++++++++++++++++++++
 xo-cmake/cmake/xo_macros/xo_cxx.cmake    | 12 ++++++
 xo-object2/src/object2/ISequence_Any.cpp |  1 +
 4 files changed, 63 insertions(+)
 create mode 100644 pkgs/xo-object2.nix

diff --git a/default.nix b/default.nix
index f4897bf6..e3139947 100644
--- a/default.nix
+++ b/default.nix
@@ -152,6 +152,7 @@ let
             xo-alloc2         = self.callPackage pkgs/xo-alloc2.nix         { stdenv = jitStdenv; buildDocs = true; };
             xo-gc             = self.callPackage pkgs/xo-gc.nix             { stdenv = jitStdenv; buildDocs = true; };
             xo-object         = self.callPackage pkgs/xo-object.nix         { stdenv = jitStdenv; };
+            xo-object2        = self.callPackage pkgs/xo-object2.nix        { stdenv = jitStdenv; };
             xo-refcnt         = self.callPackage pkgs/xo-refcnt.nix         { stdenv = jitStdenv; };
             xo-ordinaltree    = self.callPackage pkgs/xo-ordinaltree.nix    { stdenv = jitStdenv; };
             xo-pyutil         = self.callPackage pkgs/xo-pyutil.nix         { stdenv = jitStdenv; };
@@ -501,6 +502,7 @@ in
     alloc2         = pkgs.xo-alloc2;
     gc             = pkgs.xo-gc;
     object         = pkgs.xo-object;
+    object2        = pkgs.xo-object2;
     ordinaltree    = pkgs.xo-ordinaltree;
     flatstring     = pkgs.xo-flatstring;
     pyutil         = pkgs.xo-pyutil;
diff --git a/pkgs/xo-object2.nix b/pkgs/xo-object2.nix
new file mode 100644
index 00000000..93de3b0c
--- /dev/null
+++ b/pkgs/xo-object2.nix
@@ -0,0 +1,48 @@
+{
+  # nixpkgs dependencies
+  lib, stdenv, cmake, catch2,
+
+  # xo dependencies
+#  xo-webutil,
+#  xo-callback,
+#  xo-unit,
+#  xo-refcnt,
+#  xo-reflectutil,
+#  xo-alloc,
+  #  xo-randomgen,
+  xo-reflect,
+  xo-gc,
+  xo-printable2,
+  xo-facet,
+  xo-subsys,
+  xo-cmake,
+#  xo-printjson,
+#  xo-ordinaltree,
+#  xo-indentlog,
+  doCheck ? true,
+} :
+
+stdenv.mkDerivation (finalattrs:
+  {
+    name = "xo-object2";
+
+    src = ../xo-object2;
+
+    cmakeFlags = ["-DCMAKE_MODULE_PATH=${xo-cmake}/share/cmake"]
+                 ++ lib.optionals doCheck ["-DENABLE_TESTING=1"];
+
+    inherit doCheck;
+
+    nativeBuildInputs = [
+      cmake catch2
+#      xo-randomgen
+      xo-cmake
+    ];
+    propagatedBuildInputs = [
+      xo-reflect
+      xo-gc
+      xo-printable2
+      xo-subsys
+      xo-facet
+    ];
+  })
diff --git a/xo-cmake/cmake/xo_macros/xo_cxx.cmake b/xo-cmake/cmake/xo_macros/xo_cxx.cmake
index 38d01df3..9c70505a 100644
--- a/xo-cmake/cmake/xo_macros/xo_cxx.cmake
+++ b/xo-cmake/cmake/xo_macros/xo_cxx.cmake
@@ -1748,6 +1748,18 @@ function(xo_add_genfacetimpl)
         if (NOT DEFINED GF_FACET_PKG)
             message(FATAL_ERROR "xo_add_genfacetimpl: FACET_PKG or FACET_DIR required")
         else()
+            # share_${GF_FACET_PKG} is a cmake target created by xo_add_shared_library4()
+            # or similar when a facet-provider (e.g. xo-gc) builds from source in the same
+            # cmake context (XO_SUBMODULE_BUILD=True).
+            #
+            # It is NOT exported in the installed cmake
+            # config, so it won't exist when the facet package is consumed as an installed
+            # dependency (e.g. in a standalone nix build).
+            #
+            if(NOT TARGET share_${GF_FACET_PKG})
+                message(STATUS "xo_add_genfacetimpl: share_${GF_FACET_PKG} not available; skipping ${GF_TARGET}")
+                return()
+            endif()
             get_target_property(_facet_dir share_${GF_FACET_PKG} path)
             set(GF_FACET_DIR ${_facet_dir})
         endif()
diff --git a/xo-object2/src/object2/ISequence_Any.cpp b/xo-object2/src/object2/ISequence_Any.cpp
index 372571f7..77da7d31 100644
--- a/xo-object2/src/object2/ISequence_Any.cpp
+++ b/xo-object2/src/object2/ISequence_Any.cpp
@@ -3,6 +3,7 @@
  **/
 
 #include "sequence/ISequence_Any.hpp"
+#include <exception>
 #include <iostream>
 
 namespace xo {