diff --git a/cmake/modules/AddCompilerFlags.cmake b/cmake/modules/AddCompilerFlags.cmake
--- a/cmake/modules/AddCompilerFlags.cmake
+++ b/cmake/modules/AddCompilerFlags.cmake
@@ -34,6 +34,16 @@
 	endforeach()
 endmacro()
 
+function(add_cxx_compiler_flag_with_fallback TARGET_VAR FLAG FALLBACK)
+	set(TMP_FLAG ${FLAG})
+	CHECK_CXX_COMPILER_FLAG(${TMP_FLAG} FLAG_IS_SUPPORTED)
+	if(NOT FLAG_IS_SUPPORTED)
+		set(TMP_FLAG ${FALLBACK})
+	endif()
+	string(APPEND ${TARGET_VAR} "${TMP_FLAG}")
+	set(${TARGET_VAR} ${${TARGET_VAR}} PARENT_SCOPE)
+endfunction()
+
 # Note that CMake does not provide any facility to check that a linker flag is
 # supported by the compiler, but most linker will just drop any unsupported flag
 # (eventually with a warning).
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -23,25 +23,37 @@
 # We redefine here the flags to suite our needs, by overriding the built-in
 # RelWithDebInfo configuration (release with debug info).
 
-# RelWithDebInfo CFLAGS are set to -g -O2
-set(RELWITHDEBINFO_G_C_FLAG "-g")
-set(RELWITHDEBINFO_O_C_FLAG "-O2")
+# CFLAGS are set to -g -O2 for all the configurations
+set(DEFAULT_G_C_FLAG "-g")
+set(DEFAULT_O_C_FLAG "-O2")
 
 # RelWithDebInfo CXXFLAGS flags are set to -g -O2
 set(RELWITHDEBINFO_G_CXX_FLAG "-g")
 set(RELWITHDEBINFO_O_CXX_FLAG "-O2")
-set(CMAKE_C_FLAGS_RELWITHDEBINFO
-	"${RELWITHDEBINFO_G_C_FLAG} ${RELWITHDEBINFO_O_C_FLAG}")
+set(CMAKE_C_FLAGS_RELWITHDEBINFO "${DEFAULT_G_C_FLAG} ${DEFAULT_O_C_FLAG}")
 set(CMAKE_CXX_FLAGS_RELWITHDEBINFO
 	"${RELWITHDEBINFO_G_CXX_FLAG} ${RELWITHDEBINFO_O_CXX_FLAG}")
 
+# Overrides the flags for the Debug cbuild type
+include(AddCompilerFlags)
+
+# Prefer -g3, defaults to -g if unavailable
+add_cxx_compiler_flag_with_fallback(DEBUG_G_CXX_FLAG -g3 -g)
+
+# Prefer -Og, defaults to -O0 if unavailable
+add_cxx_compiler_flag_with_fallback(DEBUG_O_CXX_FLAG -Og -O0)
+
+set(CMAKE_C_FLAGS_DEBUG "${DEFAULT_G_C_FLAG} ${DEFAULT_O_C_FLAG}")
+set(CMAKE_CXX_FLAGS_DEBUG "${DEBUG_G_CXX_FLAG} ${DEBUG_O_CXX_FLAG}")
+# Define the debugging symbols DEBUG and DEBUG_LOCKORDER
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -DDEBUG -DDEBUG_LOCKORDER")
+
 # Ensure that WINDRES_PREPROC is enabled when using windres.
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	list(APPEND CMAKE_RC_FLAGS "-DWINDRES_PREPROC")
 endif()
 
 # Enable warning
-include(AddCompilerFlags)
 
 # CMake provides the POSITION_INDEPENDENT_CODE property to set PIC/PIE.
 # Unfortunately setting the -pie linker flag this way required CMake >= 3.14,