diff --git a/CMakeLists.txt b/CMakeLists.txt
index b4c6fef849..c6b5739ef3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -955,9 +955,7 @@ IF(ENABLE_LARGE_FILE_SUPPORT)
     SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /LARGEADDRESSAWARE")
     SET(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} /LARGEADDRESSAWARE")
   ELSE()
-    SET(_FILE_OFFSET_BITS 64)
-    SET(_LARGEFILE64_SOURCE TRUE)
-    SET(_LARGEFILE_SOURCE TRUE)
+    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64")
   ENDIF()
 ENDIF()