Codechange: switch to C++17 on all platforms.

CMakeLists.txt

@@ -32,14 +32,7 @@ set_directory_options()
 include(Static)
 set_static_if_needed()
 
-if(MSVC)
+set(CMAKE_CXX_STANDARD 17)
-    # C++17 for MSVC
-    set(CMAKE_CXX_STANDARD 17)
-else()
-    # C++11 for all other targets
-    set(CMAKE_CXX_STANDARD 11)
-endif()
-
 set(CMAKE_CXX_STANDARD_REQUIRED YES)
 set(CMAKE_CXX_EXTENSIONS NO)
 

COMPILING.md

@@ -83,9 +83,9 @@ make
 
 ## Supported compilers
 
-Every compiler that is supported by CMake and supports C++11, should be
+Every compiler that is supported by CMake and supports C++17, should be
 able to compile OpenTTD. As the exact list of compilers changes constantly,
-we refer to the compiler manual to see if it supports C++11, and to CMake
+we refer to the compiler manual to see if it supports C++17, and to CMake
 to see if it supports your compiler.
 
 ## Compilation of base sets