--- src/builtin.c_org	2024-02-13 10:58:20.720043720 +0000
+++ src/builtin.c	2024-02-13 11:00:30.974628372 +0000
@@ -1,5 +1,9 @@
 #ifndef __sun__
+#if defined(_AIX)       /* AIX */
+#define _XOPEN_SOURCE 600
+#elif
 # define _XOPEN_SOURCE
+#endif   /* _AIX */
 # define _XOPEN_SOURCE_EXTENDED 1
 #else
 # define _XPG6