Requiring C++20 (#800)

* Requiring C++20

* Start replacing enable_if with requires

* Replace rest of enable_if with requires, except for AdjacencyList (see comment in file)

* Replace void_t-based SFINAE by requires and concepts

* minor

* Conceptify rest of phasar

* Fix clang dep scanning in CI and Dockerfile

* Replace  PSR_CONCEPT by concept

* minor cleanup

* Remove mentions of c++17

* adapt my mail-address in readme

---------

Co-authored-by: Fabian Schiebel <fabian.schiebel@iem.fraunhofer.de>
Co-authored-by: Fabian Schiebel <fabianbs@mail.upb.de>
Co-authored-by: Fabian Schiebel <52407375+fabianbs96@users.noreply.github.com>

Author: fabianbs

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ jobs:
       fail-fast: true
       matrix:
         os: [ubuntu-24.04, ubuntu-24.04-arm]
-        compiler: [ [clang++-19, clang-19, "clang-19 libclang-rt-19-dev"] ]
+        compiler: [ [clang++-19, clang-19, "clang-19 libclang-rt-19-dev clang-tools-19"] ]
         build: [ Debug, Release, DebugLibdeps, DebugCov ]
         include:
           - build: Debug

BUILD.md

@@ -79,7 +79,7 @@ When using CMake to compile PhASAR the following optional parameters can be used
 | **PHASAR_ENABLE_PAMM** : STRING | Enable the performance measurement mechanism ('Off', 'Core' or 'Full', default is Off) |
 | **PHASAR_ENABLE_PIC** : BOOL | Build Position-Independed Code (default is ON) |
 | **PHASAR_ENABLE_WARNINGS** : BOOL | Enable compiler warnings (default is ON) |
-| **CMAKE_CXX_STANDARD** : INT|Build phasar in C++17 or C++20 mode (default is 17)|
+| **CMAKE_CXX_STANDARD** : INT|Adapt the used C++ standard (minimum required is 20)|
 
 You can use these parameters either directly or modify the installer-script `bootstrap.sh`
 

BreakingChanges.md

@@ -2,6 +2,8 @@
 
 ## development HEAD
 
+- Requiring C++20 instead of C++17
+  - Type-traits and other templates that are specialized now use `requires` instead of `enable_if`, wherever possible. This may reduce the number of (defaulted) template parameters in some cases.
 - The `AdjacencyList` struct now now has one more template argument to denote the intege-like `vertex_t` type. It is the second template argument (which previously was the EdgeType). The edge-type is now denoted by the *third* template argument.
 - The `AdjacencyList` switches from using `llvm::NoneType` as empty-node marker to `psr::EmptyType` for forward-compatibility with LLVM-16 that removes `llvm::NoneType`.
 

CMakeLists.txt

@@ -23,14 +23,14 @@ if (DEFINED LLVM_MAIN_SRC_DIR)
   set(PHASAR_IN_TREE 1)
 endif()
 
+set(PHASAR_VERSION 2510)
 if (NOT PHASAR_IN_TREE)
   project (phasar
     LANGUAGES C CXX
     DESCRIPTION "A LLVM-based static analysis framework."
-    VERSION 2510
+    VERSION ${PHASAR_VERSION}
   )
 endif ()
-set(PHASAR_VERSION ${PROJECT_VERSION})
 
 # NOTE: When we require cmake >= 3.21, we can use PROJECT_IS_TOP_LEVEL instead
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)

Dockerfile

@@ -1,9 +1,9 @@
 ARG baseimage="ubuntu:24.04"
-FROM "$baseimage" as build
+FROM "$baseimage" AS build
 
 RUN --mount=type=bind,source=./utils/InstallAptDependencies.sh,target=/InstallAptDependencies.sh \
   set -eux; \
-  ./InstallAptDependencies.sh --noninteractive tzdata clang-19 libclang-rt-19-dev
+  ./InstallAptDependencies.sh --noninteractive tzdata clang-19 libclang-rt-19-dev clang-tools-19
 
 ENV CC=/usr/bin/clang-19 \
     CXX=/usr/bin/clang++-19

README.md

@@ -2,7 +2,7 @@
 
 # PhASAR: A LLVM-based Static Analysis Framework
 
-[![C++ Standard](https://img.shields.io/badge/C++_Standard-C%2B%2B17-blue.svg?style=flat&logo=c%2B%2B)](https://isocpp.org/)
+[![C++ Standard](https://img.shields.io/badge/C++_Standard-C%2B%2B20-blue.svg?style=flat&logo=c%2B%2B)](https://isocpp.org/)
 [![GitHub license](https://img.shields.io/badge/license-MIT-blueviolet.svg)](https://raw.githubusercontent.com/secure-software-engineering/phasar/master/LICENSE.txt)
 [![GitHub Release](https://img.shields.io/github/v/release/secure-software-engineering/phasar?label=version)](https://github.com/secure-software-engineering/phasar/releases)
 
@@ -24,7 +24,7 @@ this README first.
 as well. -->
 Please also have a look on PhASAR's project directory and notice the project directory [examples](./examples/) as well as the custom tool `tools/example-tool/myphasartool.cpp`.
 
-**NEW:** You can find PhASAR's API reference [here](https://secure-software-engineering.github.io/phasar/).
+You can find PhASAR's API reference [here](https://secure-software-engineering.github.io/phasar/).
 
 
 ## Secure Software Engineering Group
@@ -34,20 +34,17 @@ PhASAR is primarily developed and maintained by the Secure Software Engineering
 PhASAR was initially developed by Philipp Dominik Schubert (@pdschubert)(<philipp.schubert@upb.de>).
 
 Currently, PhASAR is maintained by
-- Fabian Schiebel (@fabianbs96)(<fabian.schiebel@iem.fraunhofer.de>)
+- Fabian Schiebel (@fabianbs96)(<fabian.schiebel@uni-paderborn.de>)
 - Sriteja Kummita (@sritejakv)
 - Lucas Briese (@jusito)
 - Martin Mory (@MMory)(<martin.mory@upb.de>)
 - *others*
 
 ## Required Version of the C++ Standard
 
-PhASAR requires at least C++-17.
+**NEW**: PhASAR requires at least C++-20.
 
-However, building in C++20 mode is supported. You may enable this setting the cmake variable `CMAKE_CXX_STANDARD` to `20`.
-Although phasar currently does not make use of C++-20 features (except for some `concept`s behind an #ifdef border), your client application that just *uses* phasar as a library may want to use C++20 earlier.
-
-**NEW**: PhASAR supports C++20 modules as an experimental feature.
+PhASAR supports C++20 modules as an experimental feature.
 
 ## Currently Supported Version of LLVM
 

cmake/phasar_macros.cmake

@@ -279,7 +279,7 @@ function(add_phasar_library name)
     EXPORT_NAME ${component_name}
   )
 
-  target_compile_features(${name} PUBLIC cxx_std_17)
+  target_compile_features(${name} PUBLIC cxx_std_20)
 
   set(install_module)
   if(PHASAR_LIB_MODULE_FILES)

examples/use-phasar-as-library/CMakeLists.txt

@@ -2,8 +2,7 @@ cmake_minimum_required(VERSION 3.12)
 
 project(PhasarExttoolTest)
 
-set(CMAKE_EXPORT_COMPILE_COMMANDS YES)
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 

examples/use-phasar-with-fetch-content/CMakeLists.txt

@@ -2,8 +2,7 @@ cmake_minimum_required(VERSION 3.12)
 
 project(PhasarExttoolTest)
 
-set(CMAKE_EXPORT_COMPILE_COMMANDS YES)
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 

include/phasar/ControlFlow/CFGBase.h

@@ -139,10 +139,9 @@ template <typename Derived> class CFGBase : public CRTPBase<Derived> {
 
 template <typename ICF, typename Domain>
 // NOLINTNEXTLINE(readability-identifier-naming)
-PSR_CONCEPT is_cfg_v =
-    is_crtp_base_of_v<CFGBase, ICF> &&
-    std::is_same_v<typename ICF::n_t, typename Domain::n_t> &&
-    std::is_same_v<typename ICF::f_t, typename Domain::f_t>;
+concept is_cfg_v = is_crtp_base_of_v<CFGBase, ICF> &&
+                   std::is_same_v<typename ICF::n_t, typename Domain::n_t> &&
+                   std::is_same_v<typename ICF::f_t, typename Domain::f_t>;
 
 } // namespace psr