diff  ~/work/beman/optional26/.github/workflows/ci.yml ~/work/beman/iterator_interface/.github/workflows/ci.yml 
16,17d15
<           - {name: "Ubuntu Clang 17", os: ubuntu-24.04, toolchain: "clang-17", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
<           - {name: "Ubuntu Clang 18", os: ubuntu-24.04, toolchain: "clang-18", clang_version: 18, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
20,21c18,19
<           - {name: "Ubuntu GCC 12", os: ubuntu-24.04, toolchain: "gcc-12",  cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
<           - {name: "Ubuntu GCC 13", os: ubuntu-24.04, toolchain: "gcc-13",  cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
---
>           - {name: "Ubuntu Clang 18", os: ubuntu-24.04, toolchain: "clang-18", clang_version: 18, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
>           - {name: "Ubuntu Clang 17", os: ubuntu-24.04, toolchain: "clang-17", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
22a21,23
>           - {name: "Ubuntu GCC 13", os: ubuntu-24.04, toolchain: "gcc-13",  cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
>           - {name: "Ubuntu GCC 12", os: ubuntu-24.04, toolchain: "gcc-12",  cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
> 
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> 

diff  ~/work/beman/optional26/CMakePresets.json  ~/work/beman/iterator_interface/CMakePresets.json 
41a42,48
>       "name": "gcc-12",
>       "inherits": "common",
>       "displayName": "GCC 12",
>       "description": "Build with GCC 12 compilers",
>       "toolchainFile": "${sourceDir}/etc/gcc-12-toolchain.cmake"
>     },
>     {
84a92,96
>       "name": "gcc-12",
>       "inherits": "common",
>       "configurePreset": "gcc-12"
>     },
>     {
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>       "name": "gcc-12",
>       "inherits": "common",
>       "configurePreset": "gcc-12"
>     },
>     {
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>       "name": "gcc-12",
>       "steps": [
>         {
>           "type": "configure",
>           "name": "gcc-12"
>         },
>         {
>           "type": "build",
>           "name": "gcc-12"
>         },
>         {
>           "type": "test",
>           "name": "gcc-12"
>         }
>       ]
>     },
>     {
248a283
>