diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6705ef130052..6d9c325cf03c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -378,6 +378,13 @@ if(MSVC)
         CMAKE_CXX_FLAGS_RELWITHDEBINFO
     )
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4 /MP")
+    if(__BUILD_FOR_R)
+        # MSVC does not like this commit:
+        # https://github.com/wch/r-source/commit/fb52ac1a610571fcb8ac92d886b9fefcffaa7d48
+        # 
+        # and raises "error C3646: 'private_data_c': unknown override specifier"
+        add_definitions(-DR_LEGACY_RCOMPLEX)
+    endif()
     if(USE_DEBUG)
         set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /Od")
     else()