diff --git a/Makefile b/Makefile
index b8c261be..3bf15c1f 100644
--- a/Makefile
+++ b/Makefile
@@ -19,7 +19,7 @@ mandir	?= $(prefix)/man
 
 CC	?= gcc
 XCFLAGS	?=
-CFLAGS	?= -O2 -ggdb3 -Wall -Werror -Wno-unused-parameter
+CFLAGS	?= -O2 -ggdb3 -Wall -Werror -Wno-unused-parameter -DNDEBUG=1
 CFLAGS	+= -pthread $(XCFLAGS)
 
 ########################################################################
diff --git a/reopen.h b/reopen.h
index b5c85b66..bbc2fd4b 100644
--- a/reopen.h
+++ b/reopen.h
@@ -82,7 +82,7 @@
 #endif /* __must_check_result */
 
 #ifndef __hot
-#	if defined(__GNUC__) && !defined(__clang__)
+#	if defined(NDEBUG) && (defined(__GNUC__) && !defined(__clang__))
 #		define __hot __attribute__((hot, optimize("O3")))
 #	else
 #		define __hot
@@ -90,7 +90,7 @@
 #endif /* __hot */
 
 #ifndef __cold
-#	if defined(__GNUC__) && !defined(__clang__)
+#	if defined(NDEBUG) && (defined(__GNUC__) && !defined(__clang__))
 #		define __cold __attribute__((cold, optimize("Os")))
 #	elif defined(__GNUC__)
 		/* cland case, just put infrequently used functions in separate section */
@@ -101,7 +101,7 @@
 #endif /* __cold */
 
 #ifndef __flatten
-#	if defined(__GNUC__) || defined(__clang__)
+#	if defined(NDEBUG) && (defined(__GNUC__) || defined(__clang__))
 #		define __flatten __attribute__((flatten))
 #	else
 #		define __flatten