diff --git a/makefile b/makefile
index 334228e..de0064e 100644
--- a/makefile
+++ b/makefile
@@ -9,7 +9,7 @@ NAME    := mcaselector-lite
 VERSION := 0.0.0
 DEBUG   ?= 0
 CC      ?= cc
-CFLAGS  += -c -std=c17 -Wall -Wextra -Wpedantic -Ilib -MMD -MP
+CFLAGS  += -c -std=gnu99 -Wall -Wextra -Wpedantic -Ilib -MMD -MP
 LDFLAGS +=
 MARCH   ?= $(shell uname -m)
 KERNEL  ?= $(shell uname -s | tr '[:upper:]' '[:lower:]')
diff --git a/src/error.h b/src/error.h
index 9ca5140..a8ab993 100644
--- a/src/error.h
+++ b/src/error.h
@@ -4,7 +4,6 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdnoreturn.h>
 
 #include "util/atrb.h"
 
@@ -14,7 +13,7 @@ atrb_nonnull(1) atrb_format(printf, 1, 2) static inline void debug(char const*,
 atrb_nonnull(1) atrb_format(printf, 1, 2) static inline void info(char const*, ...);
 atrb_nonnull(1) atrb_format(printf, 1, 2) static inline void warn(char const*, ...);
 atrb_nonnull(1) atrb_format(printf, 1, 2) static inline void error(char const*, ...);
-atrb_nonnull(1) atrb_format(printf, 1, 2) noreturn static inline void fatal(char const*, ...);
+atrb_nonnull(1) atrb_format(printf, 1, 2) atrb_noreturn static inline void fatal(char const*, ...);
 atrb_nonnull(2) static inline void error_callback(int err, char const* const msg);
 
 // macro to write fmt vardiac args to buf
diff --git a/src/util/atrb.h b/src/util/atrb.h
index 23fbb37..3124ff2 100644
--- a/src/util/atrb.h
+++ b/src/util/atrb.h
@@ -8,6 +8,7 @@
 #define atrb_unused
 #define atrb_pure
 #define atrb_const
+#define atrb_noreturn
 #define atrb_format()
 #define atrb_nonnull()
 
@@ -34,6 +35,11 @@
 #define atrb_const __attribute__((const))
 #endif
 
+#if __has_attribute(noreturn)
+#undef atrb_noreturn
+#define atrb_noreturn __attribute__((noreturn))
+#endif
+
 #if __has_attribute(format)
 #undef atrb_format
 #define atrb_format(...) __attribute__((format(__VA_ARGS__)))