Author: Andreas Beckmann <anbe@debian.org>
Description: append to CMAKE_CXX_FLAGS, do not overwrite
Forwarded: James Price <jamesprice.dev@gmail.com>

--- a/examples/src/CMakeLists.txt
+++ b/examples/src/CMakeLists.txt
@@ -20,9 +20,9 @@ link_directories( ${OPENCL_LIB_DIR} )
 if( MSVC )
   set(CMAKE_CXX_FLAGS " -W3 /EHsc" )
 elseif( CMAKE_COMPILER_IS_GNUCXX )
-  set(CMAKE_CXX_FLAGS "-Wall" )
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall" )
 elseif( CMAKE_CXX_COMPILER_ID STREQUAL "Clang" )
-  set(CMAKE_CXX_FLAGS "-Wall" )
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall" )
 endif()
 
 add_executable(trivial ${TRIVIAL_SOURCES} ${OPENCLHPP_HEADERS})