diff --git a/tools/CMakeLists.txt b/tools/CMakeLists.txt
index dd705a2..69d8e1d 100644
--- a/tools/CMakeLists.txt
+++ b/tools/CMakeLists.txt
@@ -4,6 +4,8 @@ find_package(Threads)
 include_directories("${CMAKE_SOURCE_DIR}/include")
 include_directories(${CMAKE_BINARY_DIR})
 
+add_definitions(-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64)
+
 add_executable(osmpbf-outline osmpbf-outline.cpp)
 
 target_include_directories(osmpbf-outline SYSTEM PRIVATE ${ZLIB_INCLUDE_DIR})