diff --git a/code/qcommon/q_shared.h b/code/qcommon/q_shared.h
index 86ddb8ea..fc667c07 100644
--- a/code/qcommon/q_shared.h
+++ b/code/qcommon/q_shared.h
@@ -306,7 +306,7 @@ typedef enum {
 #define UI_INVERSE		0x00002000
 #define UI_PULSE		0x00004000
 
-#if defined(_DEBUG) && !defined(BSPC)
+#if !defined(NDEBUG) && !defined(BSPC)
 	#define HUNK_DEBUG
 #endif
 
diff --git a/code/qcommon/qcommon.h b/code/qcommon/qcommon.h
index 5753daa4..052e5026 100644
--- a/code/qcommon/qcommon.h
+++ b/code/qcommon/qcommon.h
@@ -919,7 +919,7 @@ temp file loading
 
 */
 
-#if defined(_DEBUG) && !defined(BSPC)
+#if !defined(NDEBUG) && !defined(BSPC)
 	#define ZONE_DEBUG
 #endif