From 828cb17f179632cf9320ff5b996a730320e55b96 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Sat, 29 Jun 2024 01:28:35 +0300
Subject: [PATCH 01/20] Split build production vs testing

---
 .github/workflows/ci.yml                  |  2 +-
 .gitmodules                               |  3 ---
 CMakeLists.txt                            | 18 +++++++++++++++---
 CMakePresets.json                         | 10 +++++++++-
 extern/CMakeLists.txt                     |  6 ------
 extern/googletest                         |  1 -
 src/Beman/Optional26/CMakeLists.txt       | 21 +++------------------
 src/Beman/Optional26/tests/CMakeLists.txt | 22 ++++++++++++++++++++++
 8 files changed, 50 insertions(+), 33 deletions(-)
 delete mode 100644 extern/CMakeLists.txt
 delete mode 160000 extern/googletest
 create mode 100644 src/Beman/Optional26/tests/CMakeLists.txt

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 68bd07bb..a14260bb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -66,7 +66,7 @@ jobs:
           cd .build
           echo ${{ matrix.config.cmake_args }}
           echo ${{ matrix.config.toolchain }}
-          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE=etc/${{ matrix.config.toolchain }} -B . -S ..
+          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE=etc/${{ matrix.config.toolchain }} -DCMAKE_BUILD_TESTS=true -B . -S ..
       - name: Build
         run: |
           set -x
diff --git a/.gitmodules b/.gitmodules
index 9c4e4556..b44d8c09 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,6 +1,3 @@
 [submodule "papers/wg21"]
 	path = papers/P2988/wg21
 	url = https://github.com/mpark/wg21.git
-[submodule "extern/googletest"]
-	path = extern/googletest
-	url = https://github.com/google/googletest.git
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 564e9d76..b2647469 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,18 +3,30 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-cmake_minimum_required(VERSION 3.10)
+cmake_minimum_required(VERSION 3.27)
 
 project(
   beman_optional26
   VERSION 0.0.0
   LANGUAGES CXX)
 
-enable_testing()
+cmake_policy(VERSION 3.27)
 
 set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
 
-add_subdirectory(extern)
+if("${CMAKE_BUILD_TESTS}")
+  enable_testing()
+
+  # Fetch GoogleTest
+  include(FetchContent)
+  FetchContent_Declare(
+    googletest
+    GIT_REPOSITORY https://github.com/google/googletest.git
+    GIT_TAG        f8d7d77c06936315286eb55f8de22cd23c188571 # release-1.14.0
+  )
+  FetchContent_MakeAvailable(googletest)
+endif()
+
 add_subdirectory(src)
 add_subdirectory(examples)
 
diff --git a/CMakePresets.json b/CMakePresets.json
index 40cb22a2..3f0b39f9 100644
--- a/CMakePresets.json
+++ b/CMakePresets.json
@@ -14,7 +14,8 @@
       "binaryDir": "${sourceDir}/.build/${presetName}",
       "installDir": "${sourceDir}/.install/${presetName}",
       "cacheVariables": {
-        "CMAKE_CONFIGURATION_TYPES": "RelWithDebInfo;Debug;Tsan;Asan"
+        "CMAKE_CONFIGURATION_TYPES": "RelWithDebInfo;Debug;Tsan;Asan",
+        "CMAKE_BUILD_TESTS": true
       }
     },
     {
@@ -68,26 +69,32 @@
     },
     {
       "name": "system",
+      "inherits": "common",
       "configurePreset": "system"
     },
     {
       "name": "gcc-14",
+      "inherits": "common",
       "configurePreset": "gcc-14"
     },
     {
       "name": "gcc-13",
+      "inherits": "common",
       "configurePreset": "gcc-13"
     },
     {
       "name": "clang-19",
+      "inherits": "common",
       "configurePreset": "clang-19"
     },
     {
       "name": "clang-18",
+      "inherits": "common",
       "configurePreset": "clang-18"
     },
     {
       "name": "clang-17",
+      "inherits": "common",
       "configurePreset": "clang-17"
     }
   ],
@@ -95,6 +102,7 @@
     {
       "name": "common",
       "hidden": true,
+      "configuration": "Asan",
       "output": {
         "outputOnFailure": true
       },
diff --git a/extern/CMakeLists.txt b/extern/CMakeLists.txt
deleted file mode 100644
index 31f2a6fc..00000000
--- a/extern/CMakeLists.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-# cmake-format: off
-# extern/CMakeLists.txt -*-makefile-*-
-# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-# cmake-format: on
-
-add_subdirectory(googletest EXCLUDE_FROM_ALL)
diff --git a/extern/googletest b/extern/googletest
deleted file mode 160000
index 305e5a23..00000000
--- a/extern/googletest
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 305e5a238b3c8d11266fbafd85520fb6b3184851
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index 9cdd38ac..28393cbe 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -35,21 +35,6 @@ install(
 target_link_libraries("${TARGET_LIBRARY}")
 
 # Tests
-add_executable(optional_test "")
-
-target_sources(
-  optional_test
-  PRIVATE tests/optional.t.cpp tests/optional_ref.t.cpp
-          tests/optional_monadic.t.cpp tests/optional_range_support.t.cpp
-          tests/optional_ref_monadic.t.cpp tests/detail/iterator.t.cpp)
-
-target_link_libraries(optional_test "${TARGET_LIBRARY}")
-target_link_libraries(optional_test gtest)
-target_link_libraries(optional_test gtest_main)
-
-include(GoogleTest)
-
-# Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
-# Temporary switch to gtest_add_tests and skip some Asan checks.
-enable_testing()
-gtest_add_tests(optional_test "" AUTO)
+if("${CMAKE_BUILD_TESTS}")
+  add_subdirectory(tests)
+endif()
diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
new file mode 100644
index 00000000..47df9168
--- /dev/null
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -0,0 +1,22 @@
+# cmake-format: off
+# src/Beman/Optional26/tests/CMakeLists.txt -*-makefile-*-
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+# cmake-format: on
+
+# Tests
+add_executable(optional_test "")
+
+target_sources(
+  optional_test
+  PRIVATE optional.t.cpp optional_ref.t.cpp
+          optional_monadic.t.cpp optional_range_support.t.cpp
+          optional_ref_monadic.t.cpp detail/iterator.t.cpp)
+
+target_link_libraries(optional_test "${TARGET_LIBRARY}" GTest::gtest GTest::gtest_main)
+
+include(GoogleTest)
+
+# Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
+# Temporary switch to gtest_add_tests and skip some Asan checks.
+enable_testing()
+gtest_add_tests(optional_test "" AUTO)

From 5df2e7ec9998ccdb40785c0c9725fdd59a9c73a4 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 20:10:25 +0300
Subject: [PATCH 02/20] Cleanup in CMakeLists.txt

---
 CMakeLists.txt                      | 2 +-
 src/Beman/Optional26/CMakeLists.txt | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b2647469..9503ab7a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,7 @@ cmake_policy(VERSION 3.27)
 
 set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
 
-if("${CMAKE_BUILD_TESTS}")
+if(${CMAKE_BUILD_TESTS})
   enable_testing()
 
   # Fetch GoogleTest
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index 28393cbe..d6771d72 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -35,6 +35,6 @@ install(
 target_link_libraries("${TARGET_LIBRARY}")
 
 # Tests
-if("${CMAKE_BUILD_TESTS}")
+if(${CMAKE_BUILD_TESTS})
   add_subdirectory(tests)
 endif()

From 51ef49e935b96f7ba2ff285a35fec2b00348733f Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 20:19:04 +0300
Subject: [PATCH 03/20] Switch to conditional cmake BUILD_TESTING

---
 .github/workflows/ci.yml            | 2 +-
 CMakeLists.txt                      | 6 +++++-
 CMakePresets.json                   | 3 +--
 src/Beman/Optional26/CMakeLists.txt | 2 +-
 4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a14260bb..68bd07bb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -66,7 +66,7 @@ jobs:
           cd .build
           echo ${{ matrix.config.cmake_args }}
           echo ${{ matrix.config.toolchain }}
-          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE=etc/${{ matrix.config.toolchain }} -DCMAKE_BUILD_TESTS=true -B . -S ..
+          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE=etc/${{ matrix.config.toolchain }} -B . -S ..
       - name: Build
         run: |
           set -x
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9503ab7a..032a35a9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,11 @@ cmake_policy(VERSION 3.27)
 
 set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
 
-if(${CMAKE_BUILD_TESTS})
+# Include the CTest module.
+include(CTest)
+
+# Build the tests only if enabled via the CLI flag: BUILD_TESTING.
+if(BUILD_TESTING)
   enable_testing()
 
   # Fetch GoogleTest
diff --git a/CMakePresets.json b/CMakePresets.json
index 3f0b39f9..eb05f0c9 100644
--- a/CMakePresets.json
+++ b/CMakePresets.json
@@ -14,8 +14,7 @@
       "binaryDir": "${sourceDir}/.build/${presetName}",
       "installDir": "${sourceDir}/.install/${presetName}",
       "cacheVariables": {
-        "CMAKE_CONFIGURATION_TYPES": "RelWithDebInfo;Debug;Tsan;Asan",
-        "CMAKE_BUILD_TESTS": true
+        "CMAKE_CONFIGURATION_TYPES": "RelWithDebInfo;Debug;Tsan;Asan"
       }
     },
     {
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index d6771d72..ff94803a 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -35,6 +35,6 @@ install(
 target_link_libraries("${TARGET_LIBRARY}")
 
 # Tests
-if(${CMAKE_BUILD_TESTS})
+if(BUILD_TESTING)
   add_subdirectory(tests)
 endif()

From ceb96474d910dc4884627dbc2b4c71a1f2704f3b Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 20:24:52 +0300
Subject: [PATCH 04/20] Simplify tree: avoid CMakeLists.txt files which simply
 passes control to other subdirectory

---
 CMakeLists.txt           | 2 +-
 src/Beman/CMakeLists.txt | 6 ------
 src/CMakeLists.txt       | 6 ------
 3 files changed, 1 insertion(+), 13 deletions(-)
 delete mode 100644 src/Beman/CMakeLists.txt
 delete mode 100644 src/CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 032a35a9..37cd9c12 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,7 @@ if(BUILD_TESTING)
   FetchContent_MakeAvailable(googletest)
 endif()
 
-add_subdirectory(src)
+add_subdirectory(src/Beman/Optional26)
 add_subdirectory(examples)
 
 include(GNUInstallDirs)
diff --git a/src/Beman/CMakeLists.txt b/src/Beman/CMakeLists.txt
deleted file mode 100644
index 45dfa2b8..00000000
--- a/src/Beman/CMakeLists.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-# cmake-format: off
-# src/Beman/CMakeLists.txt -*-makefile-*-
-# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-# cmake-format: on
-
-add_subdirectory(Optional26)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
deleted file mode 100644
index 5d1346f1..00000000
--- a/src/CMakeLists.txt
+++ /dev/null
@@ -1,6 +0,0 @@
-# cmake-format: off
-# src/CMakeLists.txt -*-makefile-*-
-# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-# cmake-format: on
-
-add_subdirectory(Beman)

From 0113c157f69e02a434a28b14cb88aa9a297397a7 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 21:17:21 +0300
Subject: [PATCH 05/20] Remove warnings from CI

---
 .github/workflows/ci.yml | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 68bd07bb..eebd6252 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,12 +12,12 @@ jobs:
       fail-fast: false
       matrix:
         config:
-          - {name: "Ubuntu Clang 17", os: ubuntu-24.04, toolchain: "clang-17-toolchain.cmake", clang_version: 17, installed_clang_version: 14, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
-          - {name: "Ubuntu Clang 18", os: ubuntu-24.04, toolchain: "clang-18-toolchain.cmake", clang_version: 18, installed_clang_version: 14, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
+          - {name: "Ubuntu Clang 17", os: ubuntu-24.04, toolchain: "clang-17-toolchain.cmake", 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-toolchain.cmake", clang_version: 18, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
           # Note: clang-19 + Asan setup causes errors on some platforms. Temporary skip some checks via .asan_options.
-          - {name: "Ubuntu Clang 19", os: ubuntu-24.04, toolchain: "clang-19-toolchain.cmake", clang_version: 19, installed_clang_version: 14, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" ", asan_options: "new_delete_type_mismatch=0"}
-          - {name: "Ubuntu GCC 13", os: ubuntu-24.04, toolchain: "gcc-13-toolchain.cmake", clang_version: 17, installed_clang_version: 14, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
-          - {name: "Ubuntu GCC 14", os: ubuntu-24.04, toolchain: "gcc-14-toolchain.cmake", clang_version: 17, installed_clang_version: 14, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
+          - {name: "Ubuntu Clang 19", os: ubuntu-24.04, toolchain: "clang-19-toolchain.cmake", clang_version: 19, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" ", asan_options: "new_delete_type_mismatch=0"}
+          - {name: "Ubuntu GCC 13", os: ubuntu-24.04, toolchain: "gcc-13-toolchain.cmake", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
+          - {name: "Ubuntu GCC 14", os: ubuntu-24.04, toolchain: "gcc-14-toolchain.cmake", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
     steps:
       - uses: actions/checkout@v3
         with:

From d680da6915a4fd94bd7d79fb8b60e74234b083f3 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 23:14:29 +0300
Subject: [PATCH 06/20] Remove unused cmake enable_testing

---
 CMakeLists.txt                            | 2 --
 src/Beman/Optional26/tests/CMakeLists.txt | 1 -
 2 files changed, 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37cd9c12..7653c826 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,8 +19,6 @@ include(CTest)
 
 # Build the tests only if enabled via the CLI flag: BUILD_TESTING.
 if(BUILD_TESTING)
-  enable_testing()
-
   # Fetch GoogleTest
   include(FetchContent)
   FetchContent_Declare(
diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index 47df9168..15673d71 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -18,5 +18,4 @@ include(GoogleTest)
 
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
 # Temporary switch to gtest_add_tests and skip some Asan checks.
-enable_testing()
 gtest_add_tests(optional_test "" AUTO)

From 7b4486604dc3f62e0400e77ef64121d236130d4d Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 23:15:35 +0300
Subject: [PATCH 07/20] Simplify root CMakeLists.txt

---
 CMakeLists.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7653c826..15cad5d6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,13 +14,13 @@ cmake_policy(VERSION 3.27)
 
 set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
 
-# Include the CTest module.
+# Includes
 include(CTest)
+include(FetchContent)
 
 # Build the tests only if enabled via the CLI flag: BUILD_TESTING.
 if(BUILD_TESTING)
   # Fetch GoogleTest
-  include(FetchContent)
   FetchContent_Declare(
     googletest
     GIT_REPOSITORY https://github.com/google/googletest.git

From 05f2788d133e76d7c39871f5baad3cec670100bf Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 23:18:12 +0300
Subject: [PATCH 08/20] Simplify tests CMakeLists.txt

---
 src/Beman/Optional26/tests/CMakeLists.txt | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index 15673d71..e88a9f51 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -3,19 +3,20 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-# Tests
-add_executable(optional_test "")
+include(GoogleTest)
 
-target_sources(
-  optional_test
-  PRIVATE optional.t.cpp optional_ref.t.cpp
-          optional_monadic.t.cpp optional_range_support.t.cpp
-          optional_ref_monadic.t.cpp detail/iterator.t.cpp)
+# Tests
+add_executable(optional_test
+  optional.t.cpp
+  optional_ref.t.cpp
+  optional_monadic.t.cpp
+  optional_range_support.t.cpp
+  optional_ref_monadic.t.cpp
+  detail/iterator.t.cpp
+)
 
 target_link_libraries(optional_test "${TARGET_LIBRARY}" GTest::gtest GTest::gtest_main)
 
-include(GoogleTest)
-
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
 # Temporary switch to gtest_add_tests and skip some Asan checks.
 gtest_add_tests(optional_test "" AUTO)

From d99381e9e5198aef48889e473249f7f5f4565a90 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Mon, 15 Jul 2024 23:23:48 +0300
Subject: [PATCH 09/20] Improve naming for target library in CMakeLists.txt

---
 src/Beman/Optional26/CMakeLists.txt       | 12 +++++-------
 src/Beman/Optional26/tests/CMakeLists.txt |  2 +-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index ff94803a..d44bcd36 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -3,24 +3,22 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-set(TARGET_LIBRARY "beman_optional26")
+add_library(beman_optional26 STATIC "")
 
-add_library("${TARGET_LIBRARY}" STATIC "")
-
-target_sources("${TARGET_LIBRARY}" PRIVATE optional.cpp detail/iterator.cpp)
+target_sources(beman_optional26 PRIVATE optional.cpp detail/iterator.cpp)
 
 include(GNUInstallDirs)
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 
 target_include_directories(
-  "${TARGET_LIBRARY}"
+  beman_optional26
   PUBLIC
     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../../../include>
     $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_LOWER_PROJECT_NAME}> # <prefix>/include/scratch
 )
 
 install(
-  TARGETS "${TARGET_LIBRARY}"
+  TARGETS beman_optional26
   EXPORT ${TARGETS_EXPORT_NAME}1
   DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
@@ -32,7 +30,7 @@ install(
   FILES_MATCHING
   PATTERN "*.hpp")
 
-target_link_libraries("${TARGET_LIBRARY}")
+target_link_libraries(beman_optional26)
 
 # Tests
 if(BUILD_TESTING)
diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index e88a9f51..2fc778f7 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -15,7 +15,7 @@ add_executable(optional_test
   detail/iterator.t.cpp
 )
 
-target_link_libraries(optional_test "${TARGET_LIBRARY}" GTest::gtest GTest::gtest_main)
+target_link_libraries(optional_test beman_optional26 GTest::gtest GTest::gtest_main)
 
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
 # Temporary switch to gtest_add_tests and skip some Asan checks.

From 03f85a45a88e4040082cd174befcf183615cde5f Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Tue, 16 Jul 2024 08:38:57 +0300
Subject: [PATCH 10/20] Link issue

---
 src/Beman/Optional26/tests/CMakeLists.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index 2fc778f7..b47def96 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -17,6 +17,7 @@ add_executable(optional_test
 
 target_link_libraries(optional_test beman_optional26 GTest::gtest GTest::gtest_main)
 
+# Issue #32: Re-enable ASAN run CI/clang-19
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
-# Temporary switch to gtest_add_tests and skip some Asan checks.
+# Temporary switch to gtest_add_tests and skip some Asan checks. Change also applied for CI flows.
 gtest_add_tests(optional_test "" AUTO)

From 49dd45ae4f61e2c37eb13c40f85de220a0855428 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Tue, 16 Jul 2024 08:44:24 +0300
Subject: [PATCH 11/20] More tweaks for bulding

---
 CMakeLists.txt                            |  6 ++----
 src/Beman/Optional26/CMakeLists.txt       |  7 ++++---
 src/Beman/Optional26/tests/CMakeLists.txt | 11 +++++++++--
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 15cad5d6..2187dbfc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,14 +10,12 @@ project(
   VERSION 0.0.0
   LANGUAGES CXX)
 
-cmake_policy(VERSION 3.27)
-
-set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
-
 # Includes
 include(CTest)
 include(FetchContent)
 
+set(TARGETS_EXPORT_NAME ${CMAKE_PROJECT_NAME}Targets)
+
 # Build the tests only if enabled via the CLI flag: BUILD_TESTING.
 if(BUILD_TESTING)
   # Fetch GoogleTest
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index d44bcd36..4f2e9612 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -3,9 +3,10 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-add_library(beman_optional26 STATIC "")
-
-target_sources(beman_optional26 PRIVATE optional.cpp detail/iterator.cpp)
+add_library(beman_optional26 STATIC
+  optional.cpp
+  detail/iterator.cpp
+)
 
 include(GNUInstallDirs)
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index b47def96..91c757fb 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -15,9 +15,16 @@ add_executable(optional_test
   detail/iterator.t.cpp
 )
 
-target_link_libraries(optional_test beman_optional26 GTest::gtest GTest::gtest_main)
+target_link_libraries(optional_test
+  beman_optional26
+  GTest::gtest
+  GTest::gtest_main
+)
 
 # Issue #32: Re-enable ASAN run CI/clang-19
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
 # Temporary switch to gtest_add_tests and skip some Asan checks. Change also applied for CI flows.
-gtest_add_tests(optional_test "" AUTO)
+gtest_add_tests(TARGET optional_test
+  ""
+  AUTO
+)

From 3905061c58cc0e151c75d1a30acd6b0c8e6401f7 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Tue, 16 Jul 2024 09:45:51 +0300
Subject: [PATCH 12/20] Addd build instructions

---
 README.md | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 79 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index bddf6e49..6ce794e0 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,26 @@ This repository implements `std::optional` extensions targeting C++26. The `Bema
 * [Give *std::optional* Range Support (P3168R2)](https://wg21.link/P3168R2)
 * [`std::optional<T&>` (P2988R5)](https://wg21.link/P2988R5)
 
+
+## Table of Contents
+
+- [Beman.Optional26: C++26 Extensions for std::optional](#bemanoptional26-c26-extensions-for-stdoptional)
+  - [Table of Contents](#table-of-contents)
+  - [License](#license)
+  - [Examples](#examples)
+    - [range\_loop](#range_loop)
+    - [optional\_ref](#optional_ref)
+  - [How to Build](#how-to-build)
+    - [Compiler Support](#compiler-support)
+    - [Dependencies](#dependencies)
+    - [Instructions](#instructions)
+      - [Default Build and Test Flow](#default-build-and-test-flow)
+      - [More Complex Cases](#more-complex-cases)
+      - [Step by Step Build: Build and Run Tests](#step-by-step-build-build-and-run-tests)
+      - [Step by Step Build: Build Production and Skip Tests](#step-by-step-build-build-production-and-skip-tests)
+  - [Papers](#papers)
+
+
 ## License
 
 Source is licensed with the Apache 2.0 license with LLVM exceptions
@@ -123,7 +143,7 @@ apt-get install                           \
 
 Full set of supported toolchains can be found in [.github/workflows/ci.yml](.github/workflows/ci.yml).
 
-#### Basic Build
+#### Default Build and Test Flow
 
 This project strives to be as normal and simple a CMake project as possible. This build workflow in particular will work, producing a static `beman_optional26` library, ready to package:
 
@@ -168,7 +188,7 @@ Total Test time (real) =   0.09 sec
 
 This should build and run the tests with GCC 14 with the address and undefined behavior sanitizers enabled.
 
-#### More complex cases
+#### More Complex Cases
 
 The CMake preset system suffers from combinitorial explosion. There is a makefile in the root of the repository to aid in running more configurations.
 
@@ -178,6 +198,63 @@ make -k TOOLCHAIN=clang-18  CONFIG=Tsan  VERBOSE=1
 
 The makefile will use your system compiler, `c++`, if no toolchain name is provided, otherwise it will use the toolchain in the etc/ directory to perform the build. The Ninja multi config generator is used, with configurations for `RelWithDebugInfo`, `Debug`, `Tsan`, and `Asan` configured by default.
 
+#### Step by Step Build: Build and Run Tests
+
+CI current build and test flows:
+
+```shell
+# Configure build: default build production code + tests (BUILD_TESTING=ON by default).
+$ rm -rf .build/
+$ mkdir -p .build
+$ cd .build
+$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -B . -S ..
+-- The CXX compiler identification is Clang 19.0.0
+...
+-- Build files have been written to: /home/dariusn/git/Beman/Beman.Optional26/.build
+
+# Build.
+$ cd ..
+$ cmake --build .build --config Asan --target all -- -k 0
+...
+[30/30] Linking CXX executable examples/Asan/sample
+
+# Run tests.
+$ cd .build
+$ ctest --build-config Asan --output-on-failure
+Test project /home/dariusn/git/Beman/Beman.Optional26/.build
+...
+100% tests passed, 0 tests failed out of 82
+
+Total Test time (real) =   0.67 sec
+```
+
+#### Step by Step Build: Build Production and Skip Tests
+
+By default, we build and run tests. You can provide `-DBUILD_TESTING=OFF` and completely disable building tests:
+
+```shell
+# Configure build: build production code, skip tests (BUILD_TESTING=OFF).
+$ rm -rf .build/
+$ mkdir -p .build
+$ cd .build
+$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -DBUILD_TESTING=OFF -B . -S ..
+-- The CXX compiler identification is Clang 19.0.0
+...
+-- Build files have been written to: /home/dariusn/git/Beman/Beman.Optional26/.build
+
+# Build.
+$ cd ..
+$ cmake --build .build --config Asan --target all -- -k 0
+...
+[15/15] Linking CXX executable examples/Asan/sample
+
+# Check that tests are not built/installed.
+$ cd .build
+$ ctest --build-config Asan --output-on-failure
+Test project /home/dariusn/git/Beman/Beman.Optional26/.build
+No tests were found!!!
+```
+
 ## Papers
 
 Latest revision(s) of the papers can be built / found at:

From 0282cd52b45ce94d49a955106f6e4af93c45e33c Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Tue, 16 Jul 2024 13:23:56 +0300
Subject: [PATCH 13/20] Skip Clang install for GCC target setups

---
 .github/workflows/ci.yml |  37 ++++++++-----
 Ubuntu-24.04.Dockerfile  | 114 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 138 insertions(+), 13 deletions(-)
 create mode 100644 Ubuntu-24.04.Dockerfile

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index eebd6252..66193455 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,12 +12,12 @@ jobs:
       fail-fast: false
       matrix:
         config:
-          - {name: "Ubuntu Clang 17", os: ubuntu-24.04, toolchain: "clang-17-toolchain.cmake", 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-toolchain.cmake", 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\" "}
+          - {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\" "}
           # Note: clang-19 + Asan setup causes errors on some platforms. Temporary skip some checks via .asan_options.
-          - {name: "Ubuntu Clang 19", os: ubuntu-24.04, toolchain: "clang-19-toolchain.cmake", clang_version: 19, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" ", asan_options: "new_delete_type_mismatch=0"}
-          - {name: "Ubuntu GCC 13", os: ubuntu-24.04, toolchain: "gcc-13-toolchain.cmake", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
-          - {name: "Ubuntu GCC 14", os: ubuntu-24.04, toolchain: "gcc-14-toolchain.cmake", clang_version: 17, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
+          - {name: "Ubuntu Clang 19", os: ubuntu-24.04, toolchain: "clang-19", clang_version: 19, installed_clang_version: 17, cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" ", asan_options: "new_delete_type_mismatch=0"}
+          - {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 14", os: ubuntu-24.04, toolchain: "gcc-14", cmake_args: "-G \"Ninja Multi-Config\" -DCMAKE_CONFIGURATION_TYPES=\"RelWithDebInfo;Asan\" "}
     steps:
       - uses: actions/checkout@v3
         with:
@@ -26,10 +26,11 @@ jobs:
       - name: Activate verbose shell
         run: set -x
       - name: Install LLVM+Clang
-        if: startsWith(matrix.config.os, 'ubuntu-')
+        if: startsWith(matrix.config.name, 'Ubuntu Clang')
         run: |
           set -x
           cat /etc/lsb-release
+          # Remove existing Clang installations.
           sudo apt-get remove clang-${{matrix.config.installed_clang_version}} \
             lldb-${{matrix.config.installed_clang_version}} \
             lld-${{matrix.config.installed_clang_version}} \
@@ -48,17 +49,27 @@ jobs:
             libclang-${{matrix.config.installed_clang_version}}-dev \
             libclang-cpp${{matrix.config.installed_clang_version}}-dev \
             libunwind-${{matrix.config.installed_clang_version}}-dev
+          # Install LLVM+Clang.
           wget https://apt.llvm.org/llvm.sh
           chmod +x llvm.sh
           sudo ./llvm.sh ${{matrix.config.clang_version}} all
           sudo apt-get install libc++-dev libc++1 libc++abi-dev libc++abi1
-      - name: Install GCC 14
-        if: matrix.config.name == 'Ubuntu GCC 14'
+          find /usr/lib -name libc++.so*
+          ${{matrix.config.toolchain}} --version
+      - name: Install GCC
+        if: startsWith(matrix.config.name, 'Ubuntu GCC')
         run: |
           set -x
+          # Remove existing GCC installations.
+          sudo apt-get remove gcc-13 g++-13 gcc-14 g++-14 gcc g++
           sudo apt update
-          sudo apt-get install g++-14
-      - name: Configure
+          # Install GCC.
+          GCC_VERSION=$(echo ${{matrix.config.toolchain}} | cut -d '-' -f2)
+          echo "GCC_VERSION=$GCC_VERSION"
+          sudo apt-get install g++-${GCC_VERSION} gcc-${GCC_VERSION}
+          find /usr/lib -name libstdc++.so*
+          ${{matrix.config.toolchain}} --version
+      - name: CMake Configure
         run: |
           set -x
           rm -rf .build
@@ -66,12 +77,12 @@ jobs:
           cd .build
           echo ${{ matrix.config.cmake_args }}
           echo ${{ matrix.config.toolchain }}
-          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE=etc/${{ matrix.config.toolchain }} -B . -S ..
-      - name: Build
+          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE="etc/${{ matrix.config.toolchain }}-toolchain.cmake" -B . -S ..
+      - name: CMake Build
         run: |
           set -x
           cmake --build .build --config Asan --target all -- -k 0
-      - name: Test
+      - name: CTest
         run: |
           set -x
           cd .build
diff --git a/Ubuntu-24.04.Dockerfile b/Ubuntu-24.04.Dockerfile
new file mode 100644
index 00000000..a905590d
--- /dev/null
+++ b/Ubuntu-24.04.Dockerfile
@@ -0,0 +1,114 @@
+FROM ubuntu:24.04
+
+ARG TARGETPLATFORM
+ARG RUNNER_VERSION
+ARG RUNNER_CONTAINER_HOOKS_VERSION
+# Docker and Docker Compose arguments
+ARG CHANNEL=stable
+ARG DOCKER_VERSION=24.0.7
+ARG DOCKER_COMPOSE_VERSION=v2.23.0
+ARG DUMB_INIT_VERSION=1.2.5
+ARG RUNNER_USER_UID=1001
+ARG DOCKER_GROUP_GID=121
+
+ENV DEBIAN_FRONTEND=noninteractive
+RUN apt-get update -y \
+    && apt-get install -y software-properties-common \
+    && add-apt-repository -y ppa:git-core/ppa \
+    && apt-get update -y \
+    && apt-get install -y --no-install-recommends \
+    curl \
+    ca-certificates \
+    git \
+    jq \
+    sudo \
+    unzip \
+    zip \
+    && rm -rf /var/lib/apt/lists/*
+
+# Download latest git-lfs version
+RUN curl -s https://packagecloud.io/install/repositories/github/git-lfs/script.deb.sh | bash && \
+    apt-get install -y --no-install-recommends git-lfs
+
+RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
+    && groupadd docker --gid $DOCKER_GROUP_GID \
+    && usermod -aG sudo runner \
+    && usermod -aG docker runner \
+    && echo "%sudo   ALL=(ALL:ALL) NOPASSWD:ALL" > /etc/sudoers \
+    && echo "Defaults env_keep += \"DEBIAN_FRONTEND\"" >> /etc/sudoers
+
+ENV HOME=/home/runner
+
+RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
+    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
+    && chmod +x /usr/bin/dumb-init
+
+ENV RUNNER_ASSETS_DIR=/runnertmp
+RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \
+    && mkdir -p "$RUNNER_ASSETS_DIR" \
+    && cd "$RUNNER_ASSETS_DIR" \
+    && curl -fLo runner.tar.gz https://github.com/actions/runner/releases/download/v${RUNNER_VERSION}/actions-runner-linux-${ARCH}-${RUNNER_VERSION}.tar.gz \
+    && tar xzf ./runner.tar.gz \
+    && rm runner.tar.gz \
+    && ./bin/installdependencies.sh \
+    && mv ./externals ./externalstmp \
+    # libyaml-dev is required for ruby/setup-ruby action.
+    # It is installed after installdependencies.sh and before removing /var/lib/apt/lists
+    # to avoid rerunning apt-update on its own.
+    && apt-get install -y libyaml-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+ENV RUNNER_TOOL_CACHE=/opt/hostedtoolcache
+RUN mkdir /opt/hostedtoolcache \
+    && chgrp docker /opt/hostedtoolcache \
+    && chmod g+rwx /opt/hostedtoolcache
+
+RUN cd "$RUNNER_ASSETS_DIR" \
+    && curl -fLo runner-container-hooks.zip https://github.com/actions/runner-container-hooks/releases/download/v${RUNNER_CONTAINER_HOOKS_VERSION}/actions-runner-hooks-k8s-${RUNNER_CONTAINER_HOOKS_VERSION}.zip \
+    && unzip ./runner-container-hooks.zip -d ./k8s \
+    && rm -f runner-container-hooks.zip
+
+RUN set -vx; \
+    export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
+    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && curl -fLo docker.tgz https://download.docker.com/linux/static/${CHANNEL}/${ARCH}/docker-${DOCKER_VERSION}.tgz \
+    && tar zxvf docker.tgz \
+    && install -o root -g root -m 755 docker/docker /usr/bin/docker \
+    && rm -rf docker docker.tgz
+
+RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
+    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
+    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
+    && mkdir -p /usr/libexec/docker/cli-plugins \
+    && curl -fLo /usr/libexec/docker/cli-plugins/docker-compose https://github.com/docker/compose/releases/download/${DOCKER_COMPOSE_VERSION}/docker-compose-linux-${ARCH} \
+    && chmod +x /usr/libexec/docker/cli-plugins/docker-compose \
+    && ln -s /usr/libexec/docker/cli-plugins/docker-compose /usr/bin/docker-compose \
+    && which docker-compose \
+    && docker compose version
+
+# We place the scripts in `/usr/bin` so that users who extend this image can
+# override them with scripts of the same name placed in `/usr/local/bin`.
+COPY entrypoint.sh startup.sh logger.sh graceful-stop.sh update-status /usr/bin/
+
+# Copy the docker shim which propagates the docker MTU to underlying networks
+# to replace the docker binary in the PATH.
+COPY docker-shim.sh /usr/local/bin/docker
+
+# Configure hooks folder structure.
+COPY hooks /etc/arc/hooks/
+
+# Add the Python "User Script Directory" to the PATH
+ENV PATH="${PATH}:${HOME}/.local/bin/"
+ENV ImageOS=ubuntu24
+
+RUN echo "PATH=${PATH}" > /etc/environment \
+    && echo "ImageOS=${ImageOS}" >> /etc/environment
+
+USER runner
+
+ENTRYPOINT ["/bin/bash", "-c"]
+CMD ["entrypoint.sh"]

From 8d0a51486e152085cd22ee057c67354fc9218ad8 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Tue, 16 Jul 2024 14:13:50 +0300
Subject: [PATCH 14/20] Fix Clang build on CI

---
 .github/workflows/ci.yml |  29 +++++-----
 Ubuntu-24.04.Dockerfile  | 114 ---------------------------------------
 2 files changed, 17 insertions(+), 126 deletions(-)
 delete mode 100644 Ubuntu-24.04.Dockerfile

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 66193455..2f4c7989 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -31,9 +31,9 @@ jobs:
           set -x
           cat /etc/lsb-release
           # Remove existing Clang installations.
-          sudo apt-get remove clang-${{matrix.config.installed_clang_version}} \
-            lldb-${{matrix.config.installed_clang_version}} \
-            lld-${{matrix.config.installed_clang_version}} \
+          sudo apt-get remove \
+            clang-${{matrix.config.installed_clang_version}} \
+            clang++-${{matrix.config.installed_clang_version}} \
             clangd-${{matrix.config.installed_clang_version}} \
             clang-tidy-${{matrix.config.installed_clang_version}} \
             clang-format-${{matrix.config.installed_clang_version}} \
@@ -42,20 +42,25 @@ jobs:
             lld-${{matrix.config.installed_clang_version}} \
             lldb-${{matrix.config.installed_clang_version}} \
             llvm-${{matrix.config.installed_clang_version}}-tools \
-            libomp-${{matrix.config.installed_clang_version}}-dev \
             libc++-${{matrix.config.installed_clang_version}}-dev \
             libc++abi-${{matrix.config.installed_clang_version}}-dev \
             libclang-common-${{matrix.config.installed_clang_version}}-dev \
             libclang-${{matrix.config.installed_clang_version}}-dev \
             libclang-cpp${{matrix.config.installed_clang_version}}-dev \
-            libunwind-${{matrix.config.installed_clang_version}}-dev
+            libomp-${{matrix.config.installed_clang_version}}-dev \
+            libunwind-${{matrix.config.installed_clang_version}}-dev \
+            libc++-dev libc++1 libc++abi-dev libc++abi1
           # Install LLVM+Clang.
+          CLANG_VERSION=$(echo ${{matrix.config.toolchain}} | cut -d '-' -f2)
           wget https://apt.llvm.org/llvm.sh
           chmod +x llvm.sh
-          sudo ./llvm.sh ${{matrix.config.clang_version}} all
-          sudo apt-get install libc++-dev libc++1 libc++abi-dev libc++abi1
-          find /usr/lib -name libc++.so*
-          ${{matrix.config.toolchain}} --version
+          sudo ./llvm.sh ${CLANG_VERSION} all
+          # Link Clang libraries (if not done by llvm.sh - some links are already set).
+          sudo ln -fs /usr/lib/llvm-${CLANG_VERSION}/lib/lib* /usr/lib/x86_64-linux-gnu/ || true
+          # If Clang 17, install a newer version of libc++ and libc++abi.
+          [[ ${CLANG_VERSION} = 17 ]] && sudo apt-get install libc++-dev libc++1 libc++abi-dev libc++abi1
+          find /usr/lib/x86_64-linux-gnu/ -name libc++.so* || true
+          clang++-${CLANG_VERSION} --version
       - name: Install GCC
         if: startsWith(matrix.config.name, 'Ubuntu GCC')
         run: |
@@ -67,8 +72,8 @@ jobs:
           GCC_VERSION=$(echo ${{matrix.config.toolchain}} | cut -d '-' -f2)
           echo "GCC_VERSION=$GCC_VERSION"
           sudo apt-get install g++-${GCC_VERSION} gcc-${GCC_VERSION}
-          find /usr/lib -name libstdc++.so*
-          ${{matrix.config.toolchain}} --version
+          find /usr/lib/x86_64-linux-gnu/ -name libstdc++.so*
+          g++-${GCC_VERSION} --version
       - name: CMake Configure
         run: |
           set -x
@@ -82,7 +87,7 @@ jobs:
         run: |
           set -x
           cmake --build .build --config Asan --target all -- -k 0
-      - name: CTest
+      - name: CMake Test
         run: |
           set -x
           cd .build
diff --git a/Ubuntu-24.04.Dockerfile b/Ubuntu-24.04.Dockerfile
deleted file mode 100644
index a905590d..00000000
--- a/Ubuntu-24.04.Dockerfile
+++ /dev/null
@@ -1,114 +0,0 @@
-FROM ubuntu:24.04
-
-ARG TARGETPLATFORM
-ARG RUNNER_VERSION
-ARG RUNNER_CONTAINER_HOOKS_VERSION
-# Docker and Docker Compose arguments
-ARG CHANNEL=stable
-ARG DOCKER_VERSION=24.0.7
-ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
-ARG RUNNER_USER_UID=1001
-ARG DOCKER_GROUP_GID=121
-
-ENV DEBIAN_FRONTEND=noninteractive
-RUN apt-get update -y \
-    && apt-get install -y software-properties-common \
-    && add-apt-repository -y ppa:git-core/ppa \
-    && apt-get update -y \
-    && apt-get install -y --no-install-recommends \
-    curl \
-    ca-certificates \
-    git \
-    jq \
-    sudo \
-    unzip \
-    zip \
-    && rm -rf /var/lib/apt/lists/*
-
-# Download latest git-lfs version
-RUN curl -s https://packagecloud.io/install/repositories/github/git-lfs/script.deb.sh | bash && \
-    apt-get install -y --no-install-recommends git-lfs
-
-RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
-    && groupadd docker --gid $DOCKER_GROUP_GID \
-    && usermod -aG sudo runner \
-    && usermod -aG docker runner \
-    && echo "%sudo   ALL=(ALL:ALL) NOPASSWD:ALL" > /etc/sudoers \
-    && echo "Defaults env_keep += \"DEBIAN_FRONTEND\"" >> /etc/sudoers
-
-ENV HOME=/home/runner
-
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
-ENV RUNNER_ASSETS_DIR=/runnertmp
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \
-    && mkdir -p "$RUNNER_ASSETS_DIR" \
-    && cd "$RUNNER_ASSETS_DIR" \
-    && curl -fLo runner.tar.gz https://github.com/actions/runner/releases/download/v${RUNNER_VERSION}/actions-runner-linux-${ARCH}-${RUNNER_VERSION}.tar.gz \
-    && tar xzf ./runner.tar.gz \
-    && rm runner.tar.gz \
-    && ./bin/installdependencies.sh \
-    && mv ./externals ./externalstmp \
-    # libyaml-dev is required for ruby/setup-ruby action.
-    # It is installed after installdependencies.sh and before removing /var/lib/apt/lists
-    # to avoid rerunning apt-update on its own.
-    && apt-get install -y libyaml-dev \
-    && rm -rf /var/lib/apt/lists/*
-
-ENV RUNNER_TOOL_CACHE=/opt/hostedtoolcache
-RUN mkdir /opt/hostedtoolcache \
-    && chgrp docker /opt/hostedtoolcache \
-    && chmod g+rwx /opt/hostedtoolcache
-
-RUN cd "$RUNNER_ASSETS_DIR" \
-    && curl -fLo runner-container-hooks.zip https://github.com/actions/runner-container-hooks/releases/download/v${RUNNER_CONTAINER_HOOKS_VERSION}/actions-runner-hooks-k8s-${RUNNER_CONTAINER_HOOKS_VERSION}.zip \
-    && unzip ./runner-container-hooks.zip -d ./k8s \
-    && rm -f runner-container-hooks.zip
-
-RUN set -vx; \
-    export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo docker.tgz https://download.docker.com/linux/static/${CHANNEL}/${ARCH}/docker-${DOCKER_VERSION}.tgz \
-    && tar zxvf docker.tgz \
-    && install -o root -g root -m 755 docker/docker /usr/bin/docker \
-    && rm -rf docker docker.tgz
-
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && mkdir -p /usr/libexec/docker/cli-plugins \
-    && curl -fLo /usr/libexec/docker/cli-plugins/docker-compose https://github.com/docker/compose/releases/download/${DOCKER_COMPOSE_VERSION}/docker-compose-linux-${ARCH} \
-    && chmod +x /usr/libexec/docker/cli-plugins/docker-compose \
-    && ln -s /usr/libexec/docker/cli-plugins/docker-compose /usr/bin/docker-compose \
-    && which docker-compose \
-    && docker compose version
-
-# We place the scripts in `/usr/bin` so that users who extend this image can
-# override them with scripts of the same name placed in `/usr/local/bin`.
-COPY entrypoint.sh startup.sh logger.sh graceful-stop.sh update-status /usr/bin/
-
-# Copy the docker shim which propagates the docker MTU to underlying networks
-# to replace the docker binary in the PATH.
-COPY docker-shim.sh /usr/local/bin/docker
-
-# Configure hooks folder structure.
-COPY hooks /etc/arc/hooks/
-
-# Add the Python "User Script Directory" to the PATH
-ENV PATH="${PATH}:${HOME}/.local/bin/"
-ENV ImageOS=ubuntu24
-
-RUN echo "PATH=${PATH}" > /etc/environment \
-    && echo "ImageOS=${ImageOS}" >> /etc/environment
-
-USER runner
-
-ENTRYPOINT ["/bin/bash", "-c"]
-CMD ["entrypoint.sh"]

From 456cee031797731c654d661e11e07fa669b86476 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 13:28:42 +0300
Subject: [PATCH 15/20] Rename test target

---
 src/Beman/Optional26/tests/CMakeLists.txt | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index 91c757fb..52affaef 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -6,16 +6,16 @@
 include(GoogleTest)
 
 # Tests
-add_executable(optional_test
-  optional.t.cpp
-  optional_ref.t.cpp
+add_executable(beman_optional26_test
+  detail/iterator.t.cpp
   optional_monadic.t.cpp
   optional_range_support.t.cpp
   optional_ref_monadic.t.cpp
-  detail/iterator.t.cpp
+  optional_ref.t.cpp
+  optional.t.cpp
 )
 
-target_link_libraries(optional_test
+target_link_libraries(beman_optional26_test
   beman_optional26
   GTest::gtest
   GTest::gtest_main
@@ -24,7 +24,7 @@ target_link_libraries(optional_test
 # Issue #32: Re-enable ASAN run CI/clang-19
 # Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
 # Temporary switch to gtest_add_tests and skip some Asan checks. Change also applied for CI flows.
-gtest_add_tests(TARGET optional_test
+gtest_add_tests(TARGET beman_optional26_test
   ""
   AUTO
 )

From 5f9170821f4f304ab6ac6399e6fdb16e517b2456 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 14:01:10 +0300
Subject: [PATCH 16/20] Simplify build instructions

---
 .github/workflows/ci.yml            |  9 +++------
 README.md                           | 28 ++++++++++------------------
 src/Beman/Optional26/CMakeLists.txt |  8 +++++---
 3 files changed, 18 insertions(+), 27 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2f4c7989..10a9ec2b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -77,12 +77,10 @@ jobs:
       - name: CMake Configure
         run: |
           set -x
-          rm -rf .build
-          mkdir -p .build
-          cd .build
           echo ${{ matrix.config.cmake_args }}
           echo ${{ matrix.config.toolchain }}
-          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE="etc/${{ matrix.config.toolchain }}-toolchain.cmake" -B . -S ..
+          rm -rf .build
+          cmake ${{ matrix.config.cmake_args }} -DCMAKE_TOOLCHAIN_FILE="etc/${{ matrix.config.toolchain }}-toolchain.cmake" -B .build -S .
       - name: CMake Build
         run: |
           set -x
@@ -90,6 +88,5 @@ jobs:
       - name: CMake Test
         run: |
           set -x
-          cd .build
           [[ ! -z "${{ matrix.config.asan_options }}" ]]  && export ASAN_OPTIONS="${{ matrix.config.asan_options }}"
-          ctest --build-config Asan --output-on-failure
+          ctest --build-config Asan --output-on-failure --test-dir .build
diff --git a/README.md b/README.md
index 6ce794e0..2873eceb 100644
--- a/README.md
+++ b/README.md
@@ -204,24 +204,20 @@ CI current build and test flows:
 
 ```shell
 # Configure build: default build production code + tests (BUILD_TESTING=ON by default).
-$ rm -rf .build/
-$ mkdir -p .build
-$ cd .build
-$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -B . -S ..
+$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -B .build -S .
 -- The CXX compiler identification is Clang 19.0.0
 ...
--- Build files have been written to: /home/dariusn/git/Beman/Beman.Optional26/.build
+-- Build files have been written to: /path/to/Optional26/.build
 
 # Build.
-$ cd ..
 $ cmake --build .build --config Asan --target all -- -k 0
 ...
-[30/30] Linking CXX executable examples/Asan/sample
+[30/30] Linking CXX executable ...
 
 # Run tests.
-$ cd .build
-$ ctest --build-config Asan --output-on-failure
-Test project /home/dariusn/git/Beman/Beman.Optional26/.build
+$ ctest --build-config Asan --output-on-failure --test-dir .build
+Internal ctest changing into directory: /path/to/Optional26/.build
+Test project /path/to/Optional26/.build
 ...
 100% tests passed, 0 tests failed out of 82
 
@@ -234,23 +230,19 @@ By default, we build and run tests. You can provide `-DBUILD_TESTING=OFF` and co
 
 ```shell
 # Configure build: build production code, skip tests (BUILD_TESTING=OFF).
-$ rm -rf .build/
-$ mkdir -p .build
-$ cd .build
-$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -DBUILD_TESTING=OFF -B . -S ..
+$ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan" -DCMAKE_TOOLCHAIN_FILE=etc/clang-19-toolchain.cmake -DBUILD_TESTING=OFF -B .build -S .
 -- The CXX compiler identification is Clang 19.0.0
 ...
--- Build files have been written to: /home/dariusn/git/Beman/Beman.Optional26/.build
+-- Build files have been written to: /path/to/Optional26/.build
 
 # Build.
-$ cd ..
 $ cmake --build .build --config Asan --target all -- -k 0
 ...
 [15/15] Linking CXX executable examples/Asan/sample
 
 # Check that tests are not built/installed.
-$ cd .build
-$ ctest --build-config Asan --output-on-failure
+$ ctest --build-config Asan --output-on-failure --test-dir .build
+Internal ctest changing into directory: /home/dariusn/git/Beman/Beman.Optional26/.build
 Test project /home/dariusn/git/Beman/Beman.Optional26/.build
 No tests were found!!!
 ```
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index 4f2e9612..5bc3167f 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -20,8 +20,9 @@ target_include_directories(
 
 install(
   TARGETS beman_optional26
-  EXPORT ${TARGETS_EXPORT_NAME}1
-  DESTINATION ${CMAKE_INSTALL_LIBDIR})
+  EXPORT ${TARGETS_EXPORT_NAME}
+  DESTINATION ${CMAKE_INSTALL_LIBDIR}
+)
 
 string(TOLOWER ${CMAKE_PROJECT_NAME} CMAKE_LOWER_PROJECT_NAME)
 
@@ -29,7 +30,8 @@ install(
   DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
   DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_LOWER_PROJECT_NAME}
   FILES_MATCHING
-  PATTERN "*.hpp")
+  PATTERN "*.hpp"
+)
 
 target_link_libraries(beman_optional26)
 

From c57d25066dd0726a57258acd87c1f4d68ef9fce0 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 14:10:16 +0300
Subject: [PATCH 17/20] Run linters

---
 CMakeLists.txt                            |  2 +-
 README.md                                 | 38 +++++++++++------------
 src/Beman/Optional26/CMakeLists.txt       | 11 ++-----
 src/Beman/Optional26/tests/CMakeLists.txt | 32 +++++++------------
 4 files changed, 34 insertions(+), 49 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2187dbfc..812a1903 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,7 +22,7 @@ if(BUILD_TESTING)
   FetchContent_Declare(
     googletest
     GIT_REPOSITORY https://github.com/google/googletest.git
-    GIT_TAG        f8d7d77c06936315286eb55f8de22cd23c188571 # release-1.14.0
+    GIT_TAG f8d7d77c06936315286eb55f8de22cd23c188571 # release-1.14.0
   )
   FetchContent_MakeAvailable(googletest)
 endif()
diff --git a/README.md b/README.md
index 2873eceb..ca7050cc 100644
--- a/README.md
+++ b/README.md
@@ -13,25 +13,23 @@ This repository implements `std::optional` extensions targeting C++26. The `Bema
 * [Give *std::optional* Range Support (P3168R2)](https://wg21.link/P3168R2)
 * [`std::optional<T&>` (P2988R5)](https://wg21.link/P2988R5)
 
-
 ## Table of Contents
 
-- [Beman.Optional26: C++26 Extensions for std::optional](#bemanoptional26-c26-extensions-for-stdoptional)
-  - [Table of Contents](#table-of-contents)
-  - [License](#license)
-  - [Examples](#examples)
-    - [range\_loop](#range_loop)
-    - [optional\_ref](#optional_ref)
-  - [How to Build](#how-to-build)
-    - [Compiler Support](#compiler-support)
-    - [Dependencies](#dependencies)
-    - [Instructions](#instructions)
-      - [Default Build and Test Flow](#default-build-and-test-flow)
-      - [More Complex Cases](#more-complex-cases)
-      - [Step by Step Build: Build and Run Tests](#step-by-step-build-build-and-run-tests)
-      - [Step by Step Build: Build Production and Skip Tests](#step-by-step-build-build-production-and-skip-tests)
-  - [Papers](#papers)
-
+* [Beman.Optional26: C++26 Extensions for std::optional](#bemanoptional26-c26-extensions-for-stdoptional)
+  * [Table of Contents](#table-of-contents)
+  * [License](#license)
+  * [Examples](#examples)
+    * [range\_loop](#range_loop)
+    * [optional\_ref](#optional_ref)
+  * [How to Build](#how-to-build)
+    * [Compiler Support](#compiler-support)
+    * [Dependencies](#dependencies)
+    * [Instructions](#instructions)
+      * [Default Build and Test Flow](#default-build-and-test-flow)
+      * [More Complex Cases](#more-complex-cases)
+      * [Step by Step Build: Build and Run Tests](#step-by-step-build-build-and-run-tests)
+      * [Step by Step Build: Build Production and Skip Tests](#step-by-step-build-build-production-and-skip-tests)
+  * [Papers](#papers)
 
 ## License
 
@@ -193,7 +191,7 @@ This should build and run the tests with GCC 14 with the address and undefined b
 The CMake preset system suffers from combinitorial explosion. There is a makefile in the root of the repository to aid in running more configurations.
 
 ```shell
-make -k TOOLCHAIN=clang-18  CONFIG=Tsan  VERBOSE=1
+make -k TOOLCHAIN=clang-18 CONFIG=Tsan VERBOSE=1
 ```
 
 The makefile will use your system compiler, `c++`, if no toolchain name is provided, otherwise it will use the toolchain in the etc/ directory to perform the build. The Ninja multi config generator is used, with configurations for `RelWithDebugInfo`, `Debug`, `Tsan`, and `Asan` configured by default.
@@ -212,7 +210,7 @@ $ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan
 # Build.
 $ cmake --build .build --config Asan --target all -- -k 0
 ...
-[30/30] Linking CXX executable ...
+[30/30] Linking CXX executable ... # Note: 30 targets here (including tests).
 
 # Run tests.
 $ ctest --build-config Asan --output-on-failure --test-dir .build
@@ -238,7 +236,7 @@ $ cmake -G "Ninja Multi-Config" -DCMAKE_CONFIGURATION_TYPES="RelWithDebInfo;Asan
 # Build.
 $ cmake --build .build --config Asan --target all -- -k 0
 ...
-[15/15] Linking CXX executable examples/Asan/sample
+[15/15] Linking CXX executable ... # Note: 15 targets here (tests were not built).
 
 # Check that tests are not built/installed.
 $ ctest --build-config Asan --output-on-failure --test-dir .build
diff --git a/src/Beman/Optional26/CMakeLists.txt b/src/Beman/Optional26/CMakeLists.txt
index 5bc3167f..d19018d8 100644
--- a/src/Beman/Optional26/CMakeLists.txt
+++ b/src/Beman/Optional26/CMakeLists.txt
@@ -3,10 +3,7 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-add_library(beman_optional26 STATIC
-  optional.cpp
-  detail/iterator.cpp
-)
+add_library(beman_optional26 STATIC optional.cpp detail/iterator.cpp)
 
 include(GNUInstallDirs)
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
@@ -21,8 +18,7 @@ target_include_directories(
 install(
   TARGETS beman_optional26
   EXPORT ${TARGETS_EXPORT_NAME}
-  DESTINATION ${CMAKE_INSTALL_LIBDIR}
-)
+  DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
 string(TOLOWER ${CMAKE_PROJECT_NAME} CMAKE_LOWER_PROJECT_NAME)
 
@@ -30,8 +26,7 @@ install(
   DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
   DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${CMAKE_LOWER_PROJECT_NAME}
   FILES_MATCHING
-  PATTERN "*.hpp"
-)
+  PATTERN "*.hpp")
 
 target_link_libraries(beman_optional26)
 
diff --git a/src/Beman/Optional26/tests/CMakeLists.txt b/src/Beman/Optional26/tests/CMakeLists.txt
index 52affaef..43500207 100644
--- a/src/Beman/Optional26/tests/CMakeLists.txt
+++ b/src/Beman/Optional26/tests/CMakeLists.txt
@@ -6,25 +6,17 @@
 include(GoogleTest)
 
 # Tests
-add_executable(beman_optional26_test
-  detail/iterator.t.cpp
-  optional_monadic.t.cpp
-  optional_range_support.t.cpp
-  optional_ref_monadic.t.cpp
-  optional_ref.t.cpp
-  optional.t.cpp
-)
+add_executable(
+  beman_optional26_test
+  detail/iterator.t.cpp optional_monadic.t.cpp optional_range_support.t.cpp
+  optional_ref_monadic.t.cpp optional_ref.t.cpp optional.t.cpp)
 
-target_link_libraries(beman_optional26_test
-  beman_optional26
-  GTest::gtest
-  GTest::gtest_main
-)
+target_link_libraries(beman_optional26_test beman_optional26 GTest::gtest
+                      GTest::gtest_main)
 
-# Issue #32: Re-enable ASAN run CI/clang-19
-# Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some platforms.
-# Temporary switch to gtest_add_tests and skip some Asan checks. Change also applied for CI flows.
-gtest_add_tests(TARGET beman_optional26_test
-  ""
-  AUTO
-)
+# Issue #32: Re-enable ASAN run CI/clang-19.
+#
+# Note: clang-19 + gtest_discover_tests + Asan setup causes errors on some
+# platforms. Temporary switch to gtest_add_tests and skip some Asan checks.
+# Change also applied for CI flows.
+gtest_add_tests(TARGET beman_optional26_test "" AUTO)

From 1b45f87d81df807a9dd971149d90e721a1e0ff17 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 15:40:11 +0300
Subject: [PATCH 18/20] Fix make compile

---
 Makefile | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index b27aabc4..90e38881 100755
--- a/Makefile
+++ b/Makefile
@@ -60,16 +60,17 @@ $(_build_path)/CMakeCache.txt: | $(_build_path) .gitmodules
 	ln -s $(_build_path)/compile_commands.json
 
 compile: $(_build_path)/CMakeCache.txt ## Compile the project
+	cmake $(CMAKE_FLAGS) -DCMAKE_TOOLCHAIN_FILE=etc/$(TOOLCHAIN)-toolchain.cmake -B $(_build_path) -S .
 	cmake --build $(_build_path)  --config $(CONFIG) --target all -- -k 0
 
 install: $(_build_path)/CMakeCache.txt ## Install the project
 	DESTDIR=$(abspath $(DEST)) ninja -C $(_build_path) -k 0  install
 
 ctest: $(_build_path)/CMakeCache.txt ## Run CTest on current build
-	cd $(_build_path) && ctest --output-on-failure
+	ctest --build-config $(CONFIG) --output-on-failure --test-dir $(_build_path)
 
 ctest_ : compile
-	cd $(_build_path) && ctest --output-on-failure
+	ctest --build-config $(CONFIG) --output-on-failure --test-dir $(_build_path)
 
 test: ctest_ ## Rebuild and run tests
 

From 729e2b4a05a3f5714b1b0e52b3ce72de330b7220 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 18:45:57 +0300
Subject: [PATCH 19/20] Tweaks in root Makefile for generic build and run

---
 Makefile | 61 ++++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 39 insertions(+), 22 deletions(-)

diff --git a/Makefile b/Makefile
index 90e38881..7e639d86 100755
--- a/Makefile
+++ b/Makefile
@@ -4,12 +4,25 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 # cmake-format: on
 
-INSTALL_PREFIX?=.install/
+# This Makefile is a thin wrapper around CMake. It is intended to be used.
+
+# Default target.
 PROJECT?=$(shell basename $(CURDIR))
+
+# Default install prefix.
+INSTALL_PREFIX?=.install/
+# Default build directory.
 BUILD_DIR?=.build
+# Default destination directory.
 DEST?=$(INSTALL_PREFIX)
+# Default toolchain: missing => c++ sytem tool.
+TOOLCHAIN?=
+# Default configuration: missing => Asan.
+BUILD_CONFIG?=Asan
+# Default CMake flags.
 CMAKE_FLAGS?=
 
+# Default targets.
 TARGETS := test clean all ctest
 
 export
@@ -20,25 +33,27 @@ export
 
 .gitmodules: .update-submodules
 
-CONFIG?=Asan
 
 export
 
 ifeq ($(strip $(TOOLCHAIN)),)
-	_build_name?=build-system/
-	_build_dir?=.build/
+	# Default build configuration.
+	_build_name?=toolchain/c++-system
+	_build_dir?=$(BUILD_DIR)
 	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
 	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/toolchain.cmake
 else
-	_build_name?=build-$(TOOLCHAIN)
-	_build_dir?=.build/
+	# Custom toolchain.
+	_build_name?=toolchain/$(TOOLCHAIN)
+	_build_dir?=$(BUILD_DIR)
 	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
 	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/$(TOOLCHAIN)-toolchain.cmake
 endif
 
-
+# Build path.
 _build_path?=$(_build_dir)/$(_build_name)
 
+# CMake command wrapper.
 define run_cmake =
 	cmake \
 	-G "Ninja Multi-Config" \
@@ -46,10 +61,12 @@ define run_cmake =
 	-DCMAKE_INSTALL_PREFIX=$(abspath $(INSTALL_PREFIX)) \
 	-DCMAKE_EXPORT_COMPILE_COMMANDS=1 \
 	$(_cmake_args) \
+	$(CMAKE_FLAGS) \
 	$(CURDIR)
 endef
 
-default: test
+# Default target.
+default: build test
 
 $(_build_path):
 	mkdir -p $(_build_path)
@@ -59,34 +76,34 @@ $(_build_path)/CMakeCache.txt: | $(_build_path) .gitmodules
 	-rm compile_commands.json
 	ln -s $(_build_path)/compile_commands.json
 
-compile: $(_build_path)/CMakeCache.txt ## Compile the project
-	cmake $(CMAKE_FLAGS) -DCMAKE_TOOLCHAIN_FILE=etc/$(TOOLCHAIN)-toolchain.cmake -B $(_build_path) -S .
-	cmake --build $(_build_path)  --config $(CONFIG) --target all -- -k 0
+build: $(_build_path)/CMakeCache.txt ## Compile the project.
+	cmake $(CMAKE_FLAGS) -DCMAKE_TOOLCHAIN_FILE=etc/$(TOOLCHAIN)-toolchain.cmake  -B $(_build_path) -S .
+	cmake --build $(_build_path)  --config $(BUILD_CONFIG) --target all -- -k 0
 
-install: $(_build_path)/CMakeCache.txt ## Install the project
+install: $(_build_path)/CMakeCache.txt ## Install the project.
 	DESTDIR=$(abspath $(DEST)) ninja -C $(_build_path) -k 0  install
 
-ctest: $(_build_path)/CMakeCache.txt ## Run CTest on current build
-	ctest --build-config $(CONFIG) --output-on-failure --test-dir $(_build_path)
+ctest: $(_build_path)/CMakeCache.txt ## Run CTest on current build.
+	ctest --build-config $(BUILD_CONFIG) --output-on-failure --test-dir $(_build_path)
 
-ctest_ : compile
-	ctest --build-config $(CONFIG) --output-on-failure --test-dir $(_build_path)
+ctest_ : build
+	ctest --build-config $(BUILD_CONFIG) --output-on-failure --test-dir $(_build_path)
 
-test: ctest_ ## Rebuild and run tests
+test: ctest_ ## Rebuild and run tests.
 
 cmake: |  $(_build_path)
 	cd $(_build_path) && ${run_cmake}
 
-clean: $(_build_path)/CMakeCache.txt ## Clean the build artifacts
-	cmake --build $(_build_path)  --config $(CONFIG) --target clean
+clean: $(_build_path)/CMakeCache.txt ## Clean the build artifacts, but don't delete the build directory.
+	cmake --build $(_build_path)  --config $(BUILD_CONFIG) --target clean
 
-realclean: ## Delete the build directory
+realclean: ## Delete the entire build directory.
 	rm -rf $(_build_path)
 
 env:
 	$(foreach v, $(.VARIABLES), $(info $(v) = $($(v))))
 
-.PHONY : compile install ctest ctest_ test cmake clean realclean env
+.PHONY : build install ctest ctest_ test cmake clean realclean env
 
 .PHONY: papers
 papers:
@@ -95,4 +112,4 @@ papers:
 # Help target
 .PHONY: help
 help: ## Show this help.
-	@awk 'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'  $(MAKEFILE_LIST) targets.mk | sort
+	@awk 'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'  $(MAKEFILE_LIST) | sort

From e167523ba02990b0460dad3c8d0f805935c27b86 Mon Sep 17 00:00:00 2001
From: Darius Neatu <dariusn@adobe.com>
Date: Wed, 17 Jul 2024 18:48:17 +0300
Subject: [PATCH 20/20] Temporary remove make build support

---
 Makefile  | 115 ------------------------------------------------------
 README.md |  28 +++++--------
 2 files changed, 10 insertions(+), 133 deletions(-)
 delete mode 100755 Makefile

diff --git a/Makefile b/Makefile
deleted file mode 100755
index 7e639d86..00000000
--- a/Makefile
+++ /dev/null
@@ -1,115 +0,0 @@
-#! /usr/bin/make -f
-# cmake-format: off
-# /Makefile -*-makefile-*-
-# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-# cmake-format: on
-
-# This Makefile is a thin wrapper around CMake. It is intended to be used.
-
-# Default target.
-PROJECT?=$(shell basename $(CURDIR))
-
-# Default install prefix.
-INSTALL_PREFIX?=.install/
-# Default build directory.
-BUILD_DIR?=.build
-# Default destination directory.
-DEST?=$(INSTALL_PREFIX)
-# Default toolchain: missing => c++ sytem tool.
-TOOLCHAIN?=
-# Default configuration: missing => Asan.
-BUILD_CONFIG?=Asan
-# Default CMake flags.
-CMAKE_FLAGS?=
-
-# Default targets.
-TARGETS := test clean all ctest
-
-export
-
-.update-submodules:
-	git submodule update --init --recursive
-	touch .update-submodules
-
-.gitmodules: .update-submodules
-
-
-export
-
-ifeq ($(strip $(TOOLCHAIN)),)
-	# Default build configuration.
-	_build_name?=toolchain/c++-system
-	_build_dir?=$(BUILD_DIR)
-	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
-	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/toolchain.cmake
-else
-	# Custom toolchain.
-	_build_name?=toolchain/$(TOOLCHAIN)
-	_build_dir?=$(BUILD_DIR)
-	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
-	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/$(TOOLCHAIN)-toolchain.cmake
-endif
-
-# Build path.
-_build_path?=$(_build_dir)/$(_build_name)
-
-# CMake command wrapper.
-define run_cmake =
-	cmake \
-	-G "Ninja Multi-Config" \
-	-DCMAKE_CONFIGURATION_TYPES=$(_configuration_types) \
-	-DCMAKE_INSTALL_PREFIX=$(abspath $(INSTALL_PREFIX)) \
-	-DCMAKE_EXPORT_COMPILE_COMMANDS=1 \
-	$(_cmake_args) \
-	$(CMAKE_FLAGS) \
-	$(CURDIR)
-endef
-
-# Default target.
-default: build test
-
-$(_build_path):
-	mkdir -p $(_build_path)
-
-$(_build_path)/CMakeCache.txt: | $(_build_path) .gitmodules
-	cd $(_build_path) && $(run_cmake)
-	-rm compile_commands.json
-	ln -s $(_build_path)/compile_commands.json
-
-build: $(_build_path)/CMakeCache.txt ## Compile the project.
-	cmake $(CMAKE_FLAGS) -DCMAKE_TOOLCHAIN_FILE=etc/$(TOOLCHAIN)-toolchain.cmake  -B $(_build_path) -S .
-	cmake --build $(_build_path)  --config $(BUILD_CONFIG) --target all -- -k 0
-
-install: $(_build_path)/CMakeCache.txt ## Install the project.
-	DESTDIR=$(abspath $(DEST)) ninja -C $(_build_path) -k 0  install
-
-ctest: $(_build_path)/CMakeCache.txt ## Run CTest on current build.
-	ctest --build-config $(BUILD_CONFIG) --output-on-failure --test-dir $(_build_path)
-
-ctest_ : build
-	ctest --build-config $(BUILD_CONFIG) --output-on-failure --test-dir $(_build_path)
-
-test: ctest_ ## Rebuild and run tests.
-
-cmake: |  $(_build_path)
-	cd $(_build_path) && ${run_cmake}
-
-clean: $(_build_path)/CMakeCache.txt ## Clean the build artifacts, but don't delete the build directory.
-	cmake --build $(_build_path)  --config $(BUILD_CONFIG) --target clean
-
-realclean: ## Delete the entire build directory.
-	rm -rf $(_build_path)
-
-env:
-	$(foreach v, $(.VARIABLES), $(info $(v) = $($(v))))
-
-.PHONY : build install ctest ctest_ test cmake clean realclean env
-
-.PHONY: papers
-papers:
-	$(MAKE) -C papers papers
-
-# Help target
-.PHONY: help
-help: ## Show this help.
-	@awk 'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'  $(MAKEFILE_LIST) | sort
diff --git a/README.md b/README.md
index ca7050cc..8d3a3722 100644
--- a/README.md
+++ b/README.md
@@ -25,10 +25,10 @@ This repository implements `std::optional` extensions targeting C++26. The `Bema
     * [Compiler Support](#compiler-support)
     * [Dependencies](#dependencies)
     * [Instructions](#instructions)
-      * [Default Build and Test Flow](#default-build-and-test-flow)
-      * [More Complex Cases](#more-complex-cases)
-      * [Step by Step Build: Build and Run Tests](#step-by-step-build-build-and-run-tests)
-      * [Step by Step Build: Build Production and Skip Tests](#step-by-step-build-build-production-and-skip-tests)
+      * [Preset CMake Flows](#preset-cmake-flows)
+      * [Custom CMake Flows](#custom-cmake-flows)
+        * [Build and Run Tests](#build-and-run-tests)
+        * [Build Production, but Skip Tests](#build-production-but-skip-tests)
   * [Papers](#papers)
 
 ## License
@@ -141,7 +141,7 @@ apt-get install                           \
 
 Full set of supported toolchains can be found in [.github/workflows/ci.yml](.github/workflows/ci.yml).
 
-#### Default Build and Test Flow
+#### Preset CMake Flows
 
 This project strives to be as normal and simple a CMake project as possible. This build workflow in particular will work, producing a static `beman_optional26` library, ready to package:
 
@@ -186,17 +186,9 @@ Total Test time (real) =   0.09 sec
 
 This should build and run the tests with GCC 14 with the address and undefined behavior sanitizers enabled.
 
-#### More Complex Cases
+#### Custom CMake Flows
 
-The CMake preset system suffers from combinitorial explosion. There is a makefile in the root of the repository to aid in running more configurations.
-
-```shell
-make -k TOOLCHAIN=clang-18 CONFIG=Tsan VERBOSE=1
-```
-
-The makefile will use your system compiler, `c++`, if no toolchain name is provided, otherwise it will use the toolchain in the etc/ directory to perform the build. The Ninja multi config generator is used, with configurations for `RelWithDebugInfo`, `Debug`, `Tsan`, and `Asan` configured by default.
-
-#### Step by Step Build: Build and Run Tests
+##### Build and Run Tests
 
 CI current build and test flows:
 
@@ -222,7 +214,7 @@ Test project /path/to/Optional26/.build
 Total Test time (real) =   0.67 sec
 ```
 
-#### Step by Step Build: Build Production and Skip Tests
+##### Build Production, but Skip Tests
 
 By default, we build and run tests. You can provide `-DBUILD_TESTING=OFF` and completely disable building tests:
 
@@ -240,8 +232,8 @@ $ cmake --build .build --config Asan --target all -- -k 0
 
 # Check that tests are not built/installed.
 $ ctest --build-config Asan --output-on-failure --test-dir .build
-Internal ctest changing into directory: /home/dariusn/git/Beman/Beman.Optional26/.build
-Test project /home/dariusn/git/Beman/Beman.Optional26/.build
+Internal ctest changing into directory: /path/to/Beman.Optional26/.build
+Test project /path/to/Beman.Optional26/.build
 No tests were found!!!
 ```