diff --git a/NEWS b/NEWS
index d415bbff..514a7b3f 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,7 @@
 -- Fix --enable-portable (no usage of LFS_WRAP_NONE, bug 368).
 -- Fix dct36 wrapper usage for x86-64 and NEON. Stupid (bug 367) and
    also avoid returning void.
+-- Make ARM builds work with nagging (missing feature macros for std=c99).
 
 1.32.4
 ------
diff --git a/src/libmpg123/getcpuflags_arm.c b/src/libmpg123/getcpuflags_arm.c
index 342c217c..8d0249a1 100644
--- a/src/libmpg123/getcpuflags_arm.c
+++ b/src/libmpg123/getcpuflags_arm.c
@@ -1,11 +1,17 @@
 /*
 	getcpuflags_arm: get cpuflags for ARM
 
-	copyright 1995-2014 by the mpg123 project - free software under the terms of the LGPL 2.1
+	copyright 1995-2024 by the mpg123 project - free software under the terms of the LGPL 2.1
 	see COPYING and AUTHORS files in distribution or http://mpg123.org
 	initially written by Taihei Momma
 */
 
+// For sigsetjmp, we need POSIX 2001
+#define _POSIX_C_SOURCE 200112L
+// For SA_RESTART, XSI is needed (or POSIX 2008).
+// This here should include the above, keeping that for clarity.
+#define _XOPEN_SOURCE 600
+
 #include <setjmp.h>
 #include <signal.h>
 #include "mpg123lib_intern.h"