--- a/source/Irrlicht/CMakeLists.txt
+++ b/source/Irrlicht/CMakeLists.txt
@@ -14,9 +14,6 @@
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 if(CMAKE_CXX_COMPILER_ID MATCHES "^(GNU|Clang|AppleClang)$")
-	set(CMAKE_CXX_FLAGS_RELEASE "-O3")
-	set(CMAKE_CXX_FLAGS_DEBUG "-g")
-
 	add_compile_options(-Wall -pipe -fno-exceptions -fno-rtti)
 
 	# Enable SSE for floating point math on 32-bit x86 by default