diff --git a/CMakeLists.txt b/CMakeLists.txt
index fad2c0d..cdc6d73 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,15 +22,6 @@ if (CODE_COVERAGE)
   add_definitions(-DCOVERAGE)
 endif()
 
-option(BUILD_DEBUG "build debug binaries" ON)
-if (BUILD_DEBUG)
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O0")
-  add_definitions(-DDEBUG)
-else()
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -O2")
-  add_definitions(-DNDEBUG)
-endif()
-
 option(BUILD_SANITIZE "build with address sanitizer" OFF)
 if (BUILD_SANITIZE)
   set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address")