build: start building with C++20 Standard (#2019)

Co-authored-by: Tristan Youngs <[email protected]>

.github/workflows/_build_and_package.yml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ macos-latest, macos-13, windows-latest ]
+        os: [ macos-latest, windows-latest ]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
@@ -64,7 +64,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ macos-latest, macos-13, windows-latest ]
+        os: [ macos-latest, windows-latest ]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout

.github/workflows/benchmark.yml

@@ -22,45 +22,42 @@ jobs:
         uses: actions/checkout@v4
       - name: Setup
         uses: "./.github/workflows/setup"
-      - name: Install Prerequisites
-        run: |
-          sudo apt-get update -q
-          sudo apt-get install ninja-build python3-setuptools uuid uuid-dev
-          git submodule update --init --recursive
-      - name: Install Conan
-        run: |
-          sudo pip3 install wheel
-          sudo pip3 install conan==1.*
-      - name: Retrieve ANTLR4 Java
-        run: |
-          wget https://www.antlr.org/download/antlr-${{ env.antlrVersion }}-complete.jar -O antlr4.jar
-      - name: Build
+
+      - name: Install nix
+        uses: "./.github/workflows/get-nix"
+        with:
+          target: ${{ inputs.target }}
+
+      - name: Cache Nix Store
+        uses: actions/cache@v4
+        id: nix-cache
+        with:
+          path: /tmp/nixcache
+          key: ${{ runner.os }}-${{ env.nixHash }}-nix-cache
+
+      - name: Import Nix Store Cache
+        if: "steps.nix-cache.outputs.cache-hit == 'true'"
+        shell: bash
         run: |
-          set -ex
-          mkdir build && cd build
-          cmake ../ -G "Ninja" -DBUILD_BENCHMARKS:bool=true -DANTLR_EXECUTABLE:path=`pwd`/../antlr4.jar
-          ninja
+          nix-store --import < /tmp/nixcache
+          sudo rm -rf /tmp/nixcache
+
       - name: Run benchmarks
         run: |
           set -ex
           export LD_LIBRARY_PATH=`pwd`/build/onetbb/lib
-          cd build
 
-          # Run individual benchmarks
-          for bm in benchmark_*
-          do
-            ./${bm} --benchmark_format=json > ${bm}_result.json
-          done
+          nix build -L .#benchmarks
+
+          nix run .#benchmarks > all_benchmark_results.json
 
-          # Combine benchmark results
-          jq -s '[.[] | to_entries] | flatten | reduce .[] as $dot ({}; .[$dot.key] += $dot.value)' benchmark_*.json > all_benchmark_results.json
           cat all_benchmark_results.json
       - name: Store benchmark result
         uses: rhysd/github-action-benchmark@v1
         if: ${{ github.ref_name == 'develop' }}
         with:
             tool: 'googlecpp'
-            output-file-path: build/all_benchmark_results.json
+            output-file-path: all_benchmark_results.json
             github-token: ${{ secrets.GITHUB_TOKEN }}
             auto-push: true
             comment-on-alert: true

.github/workflows/build/osx/action.yml

@@ -92,7 +92,7 @@ runs:
       conan config set storage.download_cache="${GITHUB_WORKSPACE}/.conancache"
 
       # Set minimum deployment target version
-      export MACOSX_DEPLOYMENT_TARGET=10.15
+      export MACOSX_DEPLOYMENT_TARGET=13.3
 
       # Build
       mkdir build && cd build

.github/workflows/build/windows/action.yml

@@ -7,7 +7,7 @@ inputs:
   freeTypeArchive:
     default: https://download.savannah.gnu.org/releases/freetype/freetype-2.12.1.tar.gz
   ftglRepo:
-    default: https://github.com/frankheckenbach/ftgl.git
+    default: https://github.com/disorderedmaterials/ftgl-2.4.0
   cacheOnly:
     type: boolean
     default: false

.github/workflows/qc/action.yml

@@ -4,13 +4,24 @@ runs:
   using: "composite"
   steps:
 
-  - name: Install Dependencies
+  - name: Install nix
+    uses: "./.github/workflows/get-nix"
+    with:
+      target: ${{ inputs.target }}
+
+  - name: Cache Nix Store
+    uses: actions/cache@v4
+    id: nix-cache
+    with:
+      path: /tmp/nixcache
+      key: ${{ runner.os }}-${{ env.nixHash }}-nix-cache
+
+  - name: Import Nix Store Cache
+    if: "steps.nix-cache.outputs.cache-hit == 'true'"
     shell: bash
     run: |
-      set -ex
-      sudo apt-get update
-      sudo apt-get install --yes clang-format-13 qt6-declarative-dev-tools
-      pip install cmake_format==0.6.9
+      nix-store --import < /tmp/nixcache
+      sudo rm -rf /tmp/nixcache
 
   - name: Check Conventional Commits
     # Ensure that the PR title fits the conventional commits framework
@@ -26,26 +37,26 @@ runs:
     shell: bash
     run: |
       set -ex
-      clang-format-13 --version
-      find . -type f -regex '.*\.\(c\|cpp\|h\|hpp\|hui\)' -exec clang-format-13 -i {} +
+      nix develop --command clang-format --version
+      find . -type f -regex '.*\.\(c\|cpp\|h\|hpp\|hui\)' -exec nix develop --command clang-format -i {} +
       git diff
       git diff --quiet
 
   - name: CMake Formatting
     shell: bash
     run: |
       set -ex
-      cmake-format --version
-      find . -type f -name CMakeLists.txt -exec cmake-format -i '{}' \;
+      nix develop --command cmake-format --version
+      find . -type f -name CMakeLists.txt -exec nix develop --command cmake-format -i '{}' \;
       git diff
       git diff --quiet
 
   - name: QML Formatting
     shell: bash
     run: |
       set -ex
-      /usr/lib/qt6/bin/qmlformat --version
-      find . -type f -regex '.*\.qml' -exec /usr/lib/qt6/bin/qmlformat -inw 4 '{}' \;
+      nix develop --command qmlformat --version
+      find . -type f -regex '.*\.qml' -exec nix develop --command qmlformat -inw 4 '{}' \;
       git diff
       git diff --quiet
 

CMakeLists.txt

@@ -18,7 +18,7 @@ set(CMAKE_INCLUDE_CURRENT_DIR ON)
 cmake_policy(SET CMP0020 NEW)
 
 # Request C++17 Standard Support (Required for std::optional and auto types in lambda parameters)
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 20)
 
 # Add our custom module search path
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake/Modules")
@@ -45,9 +45,6 @@ endif(CONAN)
 
 # Find core dependencies
 set(CORE_LINK_LIBS "")
-find_package(fmt REQUIRED)
-include_directories(${fmt_INCLUDE_DIRS})
-add_compile_definitions(FMT_HEADER_ONLY)
 find_package(CLI11 REQUIRED)
 include_directories(${CLI11_INCLUDE_DIRS})
 find_package(toml11 REQUIRED)
@@ -131,7 +128,7 @@ if(GUI)
                3DExtras
                QuickWidgets
                QuickControls2
-               REQUIRED
+    REQUIRED
   )
 
   # Make sure we enable automated handling of Qt files
@@ -158,6 +155,13 @@ if(WIN32)
     include_directories(${FTGL_INCLUDE_DIRS})
   endif(GUI)
 
+  # Format requires on MSVC std:c++latest, so we have to ask for C++23, despite the fact it's part of the C++20 standard.
+  set(CMAKE_CXX_STANDARD 23)
+
+  # By default, Visual Studio lies about what C++ version it's using unless you pass it a flag to tell it not to lie.  This breaks the
+  # TOML11 library, since it checks to C++ version to see if `std::result_of` has been deprecated.
+  add_definitions(/Zc:__cplusplus)
+
   # Add defines for Windows systems - NOMINMAX to prevent conflicts with std::min() and std::max() - NOGDI to prevent conflicts arising from
   # Windows defining ERROR as a global macro (used in ANTLR4)
   add_definitions(-DNOMINMAX -DNOGDI)
@@ -179,6 +183,7 @@ endif(UNIX)
 
 # -- OSX
 if(APPLE)
+  set(CMAKE_OSX_DEPLOYMENT_TARGET 13.3)
 
   list(APPEND CMAKE_BUILD_RPATH ${CMAKE_INSTALL_PREFIX}/lib)
   # Set some specific C++11 related options here (set_property below does not seem to persist)

benchmark/CMakeLists.txt

@@ -36,7 +36,7 @@ function(dissolve_add_benchmark)
 
 endfunction()
 
-set(DISSOLVE_BENCHMARK_INPUT_FILE_PATH \"${PROJECT_SOURCE_DIR}/benchmark/common/\")
+set(DISSOLVE_BENCHMARK_INPUT_FILE_PATH \"benchmark/common/\")
 configure_file(benchmarkConfig.h.in benchmarkConfig.h @ONLY)
 
 # Add benchmark subdirectories

benchmark/classes/box.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "classes/box.h"
 #include "templates/vector3.h"

benchmark/classes/region.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "classes/region.h"
 #include "classes/box.h"

benchmark/common/problems.h

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #pragma once
 

benchmark/math/array2d.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "templates/array2D.h"
 #include <benchmark/benchmark.h>

benchmark/math/array3d.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "templates/array3D.h"
 #include <benchmark/benchmark.h>

benchmark/math/fourier.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "math/data1D.h"
 #include "math/ft.h"

benchmark/math/histogram.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "math/histogram1D.h"
 #include "math/histogram2D.h"

benchmark/math/interpolator.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "math/interpolator.h"
 #include "math/data1D.h"

benchmark/modules/angle.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/angle/angle.h"
 #include "common/problems.h"

benchmark/modules/energy.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/energy/energy.h"
 #include "common/problems.h"

benchmark/modules/forces.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/forces/forces.h"
 #include "classes/cell.h"

benchmark/modules/gr.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/gr/gr.h"
 #include "benchmark/benchmark.h"

benchmark/modules/siteRDF.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/siteRDF/siteRDF.h"
 #include "common/problems.h"

benchmark/modules/voxelDensity.cpp

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-// Copyright (c) 2024 Team Dissolve and contributors
+// Copyright (c) 2025 Team Dissolve and contributors
 
 #include "modules/voxelDensity/voxelDensity.h"
 #include "common/problems.h"

ci/windows/Dockerfile

@@ -61,7 +61,7 @@ RUN powershell -NoProfile -ExecutionPolicy Bypass -Command \
 	$env:INCLUDE += 'C:\freetype-2.10.1\' ; \
 	$env:LIB += 'C:\build\freetype' ; \
 	Echo 'Compiling FTGL' ; \
-	git clone 'https://github.com/frankheckenbach/ftgl.git' C:\ftgl-latest ; \
+	git clone 'https://github.com/disorderedmaterials/ftgl-2.4.0' C:\ftgl-latest ; \
 	cd C:\build ; \
 	mkdir ftgl ; \
 	cd ftgl ; \

cmake/Modules/conan-dissolve.cmake

@@ -8,7 +8,6 @@ include(${CMAKE_BINARY_DIR}/conan.cmake)
 # Set basic requirements and options
 set(_conan_requires
     cli11/1.9.1
-    fmt/8.1.1
     pugixml/1.11
     onetbb/2021.10.0
     onedpl/2022.3.0