--- cmake/modules/SetupBuildFlags.cmake.orig 2017-09-10 19:39:41.000000000 -0700 +++ cmake/modules/SetupBuildFlags.cmake 2017-09-10 19:40:02.000000000 -0700 @@ -78,8 +78,8 @@ endif(CMAKE_CXX_COMPILER_ID) if(("${CMAKE_C_COMPILER_ID}" STREQUAL "Clang") OR ("${CMAKE_C_COMPILER_ID}" STREQUAL "GNU") AND (NOT ${CMAKE_SYSTEM_NAME} MATCHES "BSD")) - set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--no-undefined") - set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,--no-undefined") - set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--no-undefined") + set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-undefined,error") + set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-undefined,error") + set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-undefined,error") endif(("${CMAKE_C_COMPILER_ID}" STREQUAL "Clang") OR ("${CMAKE_C_COMPILER_ID}" STREQUAL "GNU") AND (NOT ${CMAKE_SYSTEM_NAME} MATCHES "BSD")) endmacro()