diff --git a/cmake/ToywasmConfig.cmake b/cmake/ToywasmConfig.cmake
index bb0f09b2..399fe077 100644
--- a/cmake/ToywasmConfig.cmake
+++ b/cmake/ToywasmConfig.cmake
@@ -153,7 +153,11 @@ cmake_dependent_option(TOYWASM_ENABLE_DYLD_DLFCN
 option(TOYWASM_BUILD_UNITTEST "Build toywasm-test" ON)
 
 if(NOT DEFINED USE_LSAN)
+if(CMAKE_BUILD_TYPE MATCHES "Debug")
 set(USE_LSAN ON)
+else()
+set(USE_LSAN OFF)
+endif()
 endif()
 if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
 if(NOT BREW_CLANG)
@@ -284,7 +288,7 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wthread-safety")
 endif()
 
 if(NOT DEFINED USE_UBSAN)
-if(CMAKE_C_COMPILER_ID MATCHES "Clang")
+if(CMAKE_C_COMPILER_ID MATCHES "Clang" AND CMAKE_BUILD_TYPE MATCHES "Debug")
 set(USE_UBSAN ON)
 else()
 set(USE_UBSAN OFF)
@@ -308,7 +312,11 @@ list(APPEND SANITIZER_FLAGS "-fno-sanitize=pointer-overflow")
 endif()
 
 if(NOT DEFINED USE_ASAN)
+if(CMAKE_BUILD_TYPE MATCHES "Debug")
 set(USE_ASAN ON)
+else()
+set(USE_ASAN OFF)
+endif()
 endif()
 if(USE_ASAN)
 list(APPEND SANITIZER_FLAGS "-fsanitize=address")
@@ -322,7 +330,7 @@ set(ASAN_DETECT_LEAKS 0)
 endif()
 
 list(JOIN SANITIZER_FLAGS " " SANITIZER_FLAGS_STR)
-set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} ${SANITIZER_FLAGS_STR}")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${SANITIZER_FLAGS_STR}")
 
 if(NOT DEFINED USE_IPO)
 check_ipo_supported(RESULT HAVE_IPO)