Fixed clang documentation warnings

Don't warn about \threadsafety, which was added as custom documentation for SDL functions

Also removed -Wdocumentation-unknown-command, since that triggers on the e-mail addresses in the generated wayland protocol headers.

CMakeLists.txt

@@ -587,18 +587,7 @@ if(USE_GCC OR USE_CLANG)
         target_compile_options(sdl-global-options INTERFACE "-Werror=documentation")
       endif()
     endif()
-    target_compile_options(sdl-global-options INTERFACE "-Wdocumentation")
-  endif()
-
-  check_c_compiler_flag(-Wdocumentation-unknown-command HAVE_GCC_WDOCUMENTATION_UNKNOWN_COMMAND)
-  if(HAVE_GCC_WDOCUMENTATION_UNKNOWN_COMMAND)
-    if(SDL_WERROR)
-      check_c_compiler_flag(-Werror=documentation-unknown-command HAVE_GCC_WERROR_DOCUMENTATION_UNKNOWN_COMMAND)
-      if(HAVE_GCC_WERROR_DOCUMENTATION_UNKNOWN_COMMAND)
-        target_compile_options(sdl-global-options INTERFACE "-Werror=documentation-unknown-command")
-      endif()
-    endif()
-    target_compile_options(sdl-global-options INTERFACE "-Wdocumentation-unknown-command")
+    target_compile_options(sdl-global-options INTERFACE "-Wdocumentation;-fcomment-block-commands=threadsafety")
   endif()
 
   if(DEPENDENCY_TRACKING)