diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8673729..a742b49 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,7 +25,7 @@
     # note: starting with CMake 2.8 we could use CMAKE_C_COMPILER_VERSION
     execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion
                     OUTPUT_VARIABLE GCC_VERSION)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wshadow")
     if (GCC_VERSION VERSION_GREATER 4.5 OR GCC_VERSION VERSION_EQUAL 4.5)
         set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wlogical-op")
     endif()
@@ -39,7 +39,7 @@
 endif(CMAKE_COMPILER_IS_GNUCC)
 
 if(CMAKE_COMPILER_IS_CLANG)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -W -Wdeclaration-after-statement -Wwrite-strings -Wpointer-arith -Wimplicit-fallthrough -Wshadow")
     set(CMAKE_C_FLAGS_RELEASE     "-O2")
     set(CMAKE_C_FLAGS_DEBUG       "-O0 -g3")
     set(CMAKE_C_FLAGS_COVERAGE    "-O0 -g3 --coverage")