diff --git a/rocrtst/samples/CMakeLists.txt b/rocrtst/samples/CMakeLists.txt
index aed6556c33..fa74c44eef 100755
--- a/rocrtst/samples/CMakeLists.txt
+++ b/rocrtst/samples/CMakeLists.txt
@@ -179,8 +179,7 @@ add_definitions(-DLITTLEENDIAN_CPU=1)
 #
 # Linux Compiler options
 #
-set(CMAKE_CXX_FLAGS "-std=c++11 ")
-
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-math-errno")
diff --git a/rocrtst/suites/test_common/CMakeLists.txt b/rocrtst/suites/test_common/CMakeLists.txt
index 0c33db2c10..2f70ae5b69 100755
--- a/rocrtst/suites/test_common/CMakeLists.txt
+++ b/rocrtst/suites/test_common/CMakeLists.txt
@@ -201,8 +201,7 @@ add_definitions(-DLITTLEENDIAN_CPU=1)
 #
 # Linux Compiler options
 #
-set(CMAKE_CXX_FLAGS "-std=c++11 ")
-
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 ")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-math-errno")