diff --git a/cmake/modules/AddCompilerFlags.cmake b/cmake/modules/AddCompilerFlags.cmake
--- a/cmake/modules/AddCompilerFlags.cmake
+++ b/cmake/modules/AddCompilerFlags.cmake
@@ -74,6 +74,24 @@
 	remove_cxx_compiler_flags(${ARGN})
 endmacro()
 
+function(add_cxx_compiler_flag_with_fallback TARGET_VAR FLAG FALLBACK)
+	# Remove the fallback flag if it exists, so that the main flag will override
+	# it if it was previously added.
+	remove_cxx_compiler_flags(${FALLBACK})
+	
+	set(FLAG_CANDIDATE ${FLAG})
+	check_compiler_flag(FLAG_IS_SUPPORTED CXX ${FLAG_CANDIDATE})
+	if(NOT ${FLAG_IS_SUPPORTED})
+		set(FLAG_CANDIDATE ${FALLBACK})
+		check_compiler_flag(FLAG_IS_SUPPORTED CXX ${FLAG_CANDIDATE})
+	endif()
+	
+	if(${FLAG_IS_SUPPORTED})
+		string(APPEND ${TARGET_VAR} " ${FLAG_CANDIDATE}")
+		set(${TARGET_VAR} ${${TARGET_VAR}} PARENT_SCOPE)
+	endif()
+endfunction()
+
 # Note that CMake does not provide any facility to check that a linker flag is
 # supported by the compiler.
 # However since CMake 3.2 introduced the CMP0056 policy, the
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -25,6 +25,18 @@
 include(AddCompilerFlags)
 remove_compiler_flags(-DNDEBUG)
 
+# Overrides the flags for the Debug build type
+# This mimics the autotools behavior by setting the CFLAGS to '-g -O2`, which
+# are not well suited for debugging.
+# FIXME: update CFLAGS with better debug oriented optimization flags
+set(CMAKE_C_FLAGS_DEBUG "-g -O2")
+
+# Prefer -g3, defaults to -g if unavailable
+add_cxx_compiler_flag_with_fallback(CMAKE_CXX_FLAGS_DEBUG -g3 -g)
+
+# Prefer -Og, defaults to -O0 if unavailable
+add_cxx_compiler_flag_with_fallback(CMAKE_CXX_FLAGS_DEBUG -Og -O0)
+
 # Ensure that WINDRES_PREPROC is enabled when using windres.
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
 	list(APPEND CMAKE_RC_FLAGS "-DWINDRES_PREPROC")