From b44ecdcbfdf4ee1eca2fdb431dfb7dfd63cc8b1f Mon Sep 17 00:00:00 2001
From: Andreas Sturmlechner <asturm@gentoo.org>
Date: Tue, 21 Jan 2025 21:37:28 +0100
Subject: [PATCH] CMake: Cleanup CompilerSettings.cmake

>C++11 is a given, so don't tie down to now old standard;
fixes build w/ boost-1.87

Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>
---
 build_files/Modules/CompilerSettings.cmake | 49 ++++------------------
 1 file changed, 8 insertions(+), 41 deletions(-)

diff --git a/build_files/Modules/CompilerSettings.cmake b/build_files/Modules/CompilerSettings.cmake
index 76dbc219..5e25a718 100644
--- a/build_files/Modules/CompilerSettings.cmake
+++ b/build_files/Modules/CompilerSettings.cmake
@@ -9,53 +9,20 @@ ADD_DEFINITIONS(-march=core2)
 ENDIF()
 ENDIF()
 
-#Activate C++11 support, when available
-if("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
-    add_definitions(-DBRANCH_PREDICTION)
-    execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION)
-    if (GCC_VERSION VERSION_GREATER 4.7 OR GCC_VERSION VERSION_EQUAL 4.7)
-        message(STATUS "C++11 activated for GCC ${GCC_VERSION}")
-        set(CMAKE_CXX_STANDARD 11)
-        add_definitions(-DLHDR_CXX11_ENABLED)
-    elseif(GCC_VERSION VERSION_GREATER 4.3 OR GCC_VERSION VERSION_EQUAL 4.3)
-        message(WARNING "C++0x activated for GCC ${GCC_VERSION}. If you get any errors update to a compiler that fully supports C++11")
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++0x")  # add_definitions("-std=gnu++0x")
-        add_definitions(-DLHDR_CXX11_ENABLED)
-    else()
-        message(WARNING "C++11 NOT available. GCC >= 4.3 is needed.")
-    endif()
-elseif("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
-    message(STATUS "C++11 activated for Clang")
-    set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD 20)
+add_definitions(-DLHDR_CXX11_ENABLED)
+add_definitions(-DBRANCH_PREDICTION)
+if("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
     if (APPLE)
         set(CMAKE_EXE_LINKER_FLAGS "-lc++abi -stdlib=libc++ -rpath @loader_path/../Frameworks/")
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
     endif()
-    add_definitions(-DLHDR_CXX11_ENABLED)
-    add_definitions(-DBRANCH_PREDICTION)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wnull-dereference -Wdelete-non-virtual-dtor -Wsign-compare -Wswitch")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wreturn-type -Wself-assign -Wunused-argument -Wunused-function -Wtautological-compare")
-    #OpenMP support under Linux with clang
-    if (UNIX)
-        FIND_PACKAGE(OpenMP REQUIRED)
-        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
-        SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
-    endif()
-elseif(MSVC)
-    message(STATUS "C++11 is active by default on Microsoft Visual Studio")
-    add_definitions(-DLHDR_CXX11_ENABLED)
-else()
-    message(WARNING "Your C++ compiler does not support C++11.")
 endif()
-#OpenMP Support under Linux, Windows with MSVC & MacOS X with GCC >= 4.3
-IF(MSVC)
-    FIND_PACKAGE(OpenMP REQUIRED)
-    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
-    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
-ELSEIF(CMAKE_COMPILER_IS_GNUCC AND UNIX)
-    EXECUTE_PROCESS(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION)
-    IF(GCC_VERSION VERSION_GREATER 4.3 OR GCC_VERSION VERSION_EQUAL 4.3)
-        MESSAGE(STATUS "GCC >= 4.3")
+
+OPTION(USE_OPENMP "Use openmp threading support." ON)
+IF(USE_OPENMP)
+    IF(MSVC OR UNIX)
         FIND_PACKAGE(OpenMP REQUIRED)
         SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
         SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
-- 
2.45.3