diff --git a/CMakeLists.txt b/CMakeLists.txt
index 16ac322ebdd..2939d33c4a8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1430,7 +1430,6 @@ if(CMAKE_COMPILER_IS_GNUCC)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_NO_DIV_BY_ZERO -Wno-div-by-zero)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_TYPE_LIMITS -Wtype-limits)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_ERROR_RETURN_TYPE  -Werror=return-type)
-  ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_ERROR_IMPLICIT_FUNCTION_DECLARATION -Werror=implicit-function-declaration)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_NO_CHAR_SUBSCRIPTS -Wno-char-subscripts)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_NO_UNKNOWN_PRAGMAS -Wno-unknown-pragmas)
   ADD_CHECK_CXX_COMPILER_FLAG(CXX_WARNINGS CXX_WARN_POINTER_ARITH -Wpointer-arith)