--- a/jdk/src/solaris/native/sun/nio/ch/NativeThread.c	2026-10-16 23:11:22.456685548 +0100
+++ b/jdk/src/solaris/native/sun/nio/ch/NativeThread.c	2026-10-16 23:11:22.467902490 +0100
@@ -35,6 +35,9 @@
 #ifdef __linux__
   #include <pthread.h>
   #include <sys/signal.h>
+  #ifndef __SIGRTMAX
+    #define __SIGRTMAX SIGRTMAX
+  #endif
   /* Also defined in net/linux_close.c */
   #define INTERRUPT_SIGNAL (__SIGRTMAX - 2)
 #elif __solaris__
--- a/jdk/src/solaris/native/java/net/linux_close.c	2026-10-16 23:11:22.459183025 +0100
+++ b/jdk/src/solaris/native/java/net/linux_close.c	2026-10-16 23:11:22.467997266 +0100
@@ -39,6 +39,10 @@
 #include <sys/poll.h>
 #include "jvm.h"
 
+#ifndef __SIGRTMAX
+#define __SIGRTMAX SIGRTMAX
+#endif
+
 /*
  * Stack allocated by thread when doing blocking operation
  */