diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 80f21a00a..4c71d418d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -658,7 +658,7 @@ else()
 	else()
 		set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3 -fomit-frame-pointer")
 	endif(APPLE)
-	set(CMAKE_CXX_FLAGS_DEBUG "-g -O0 -Wall ${WARNING_FLAGS} ${OTHER_FLAGS}")
+	set(CMAKE_CXX_FLAGS_DEBUG "-g -O1 -Wall ${WARNING_FLAGS} ${OTHER_FLAGS}")
 
 	if(USE_GPROF)
 		set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -pg")