Bake iOS deployment version into cmakelists

Author: timothyschoen

CMakeLists.txt

@@ -46,11 +46,13 @@ endfunction()
 
 if(APPLE)
   set(CMAKE_XCODE_BUILD_SYSTEM "12" CACHE STRING "" FORCE)
-  if(MACOS_LEGACY)
-    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.11" CACHE STRING "Minimum OS X deployment version")
+  if("${CMAKE_SYSTEM_NAME}" MATCHES "iOS")
+    set(CMAKE_OSX_DEPLOYMENT_TARGET "12.0" CACHE STRING "Minimum iOS deployment version")
+  elif(MACOS_LEGACY)
+    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.11" CACHE STRING "Minimum macOS deployment version")
     set(CMAKE_OSX_ARCHITECTURES "x86_64;" CACHE STRING "" FORCE)
   else()
-    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.15" CACHE STRING "Minimum OS X deployment version")
+    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.15" CACHE STRING "Minimum macOS deployment version")
     set(CMAKE_OSX_ARCHITECTURES "arm64;x86_64" CACHE STRING "" FORCE)
   endif()