Merge pull request #3751 from JanVogelsang/pynest-ng-cpp20

Bump C++ standard to C++20

Author: heplesser

.github/workflows/nestbuildmatrix.yml

@@ -111,7 +111,7 @@ jobs:
 
       - name: "Run cppcheck..."
         run: |
-          cppcheck --enable=all --language=c++ --std=c++17 -i sli/ --suppressions-list=.cppcheck_suppressions ./
+          cppcheck --enable=all --language=c++ --std=c++20 -i sli/ --suppressions-list=.cppcheck_suppressions ./
 
   rstcheck:
     runs-on: "ubuntu-22.04"

CMakeLists.txt

@@ -24,9 +24,9 @@ list( APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake )
 
 project( nest CXX C )
 
-set( CMAKE_CXX_STANDARD 17 )
+set( CMAKE_CXX_STANDARD 20 )
 set( CMAKE_CXX_STANDARD_REQUIRED True )
-set( CMAKE_CXX_EXTENSIONS OFF )          # -std=c++17 instead of gnu++17
+set( CMAKE_CXX_EXTENSIONS OFF )          # -std=c++20 instead of gnu++20
 
 set( NEST_USER_EMAIL "users@nest-simulator.org" )
 

doc/htmldoc/developer_space/workflows/nest_with_ides.rst

@@ -148,7 +148,7 @@ Setting up the project
 
    a. *Cmake: Build Directory* to ``${workspaceFolder}/../build``
    #. *Cmake: Install Prefix* to ``${workspaceFolder}/../build/install``
-   #. *Cpp Standard* to ``c++17``
+   #. *Cpp Standard* to ``c++20``
 
 #. In the source directory, open ``.vscode/c_cpp_properties.json``, and add
 

doc/htmldoc/whats_new/v3.10/index.rst

@@ -235,6 +235,14 @@ New NEST
    }
 
 
+NEST requires C++20
+-------------------
+
+From NEST 3.10 on, we use some C++20 features in NEST code. Therefore,
+NEST needs to be built with a compiler that supports C++20. Most
+recent C++ compilers should do so.
+
+
 Model improvements
 ------------------