Index: engine/configure.ac
===================================================================
--- engine/configure.ac	(revision 827)
+++ engine/configure.ac	(working copy)
@@ -52,7 +52,7 @@
 # Enable debug
 build_flags=""
 if test "$enable_debug" = yes; then
-  build_flags="$build_flags -O0 -g -Wall -Wno-unknown-pragmas -Wparentheses -Werror"
+  build_flags="$build_flags -D_DEBUG"
 else
   build_flags="$build_flags -DNDEBUG"
 fi