commit 5d26efe38f3ed5112788ac462b293809530acbce
author Raul Tambre <raul@tambre.ee> Sat Jun 13 11:13:55 2020 +0300
committer Raul Tambre <raul@tambre.ee> Sat Jun 13 11:29:51 2020 +0300
tree 3c920950b1bfe4a26f9eca57a5f78a6b7af1bea0
parent 594fda9c234915669dbfe61bec7c59250e747b4a

Clang: Add final C++20 flag for Clang 11.0+

-std=c++20 superseded -std=c++2a in upstream Clang commit
24ad121582454e625bdad125c90d9ac0dae948c8.

Modules/Compiler/Clang.cmake

diff --git a/Modules/Compiler/Clang.cmake b/Modules/Compiler/Clang.cmake
index cd47aa6..b84bdb2 100644
--- a/Modules/Compiler/Clang.cmake
+++ b/Modules/Compiler/Clang.cmake
@@ -146,7 +146,10 @@
       set(CMAKE_${lang}17_EXTENSION_COMPILE_OPTION "-std=gnu++1z")
     endif()
 
-    if (NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS "${_clang_version_std17}")
+    if(NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 11.0)
+      set(CMAKE_${lang}20_STANDARD_COMPILE_OPTION "-std=c++20")
+      set(CMAKE_${lang}20_EXTENSION_COMPILE_OPTION "-std=gnu++20")
+    elseif(NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS "${_clang_version_std17}")
       set(CMAKE_${lang}20_STANDARD_COMPILE_OPTION "-std=c++2a")
       set(CMAKE_${lang}20_EXTENSION_COMPILE_OPTION "-std=gnu++2a")
     endif()