diff --git a/CMakeLists.txt b/CMakeLists.txt
index 644df24..ce11bd1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,8 +53,10 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
   add_definitions(-D_HAS_EXCEPTIONS=0)
 
   # Disable RTTI.
-  string(REGEX REPLACE "/GR" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /GR-")
+  if (NOT CMAKE_SYSTEM_NAME MATCHES "FreeBSD") # devel/folly requires RTTI info, see https://github.com/facebook/folly/issues/1606
+    string(REGEX REPLACE "/GR" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /GR-")
+  endif()
 else(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
   # Use -Wall for clang and gcc.
   if(NOT CMAKE_CXX_FLAGS MATCHES "-Wall")
@@ -83,8 +85,10 @@ else(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-exceptions")
 
   # Disable RTTI.
-  string(REGEX REPLACE "-frtti" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
+  if (NOT CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
+    string(REGEX REPLACE "-frtti" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
+  endif()
 endif(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
 
 # BUILD_SHARED_LIBS is a standard CMake variable, but we declare it here to make