diff --git a/include/gdbstub/syscalls.h b/include/gdbstub/syscalls.h
index d63228e96b..6200416f77 100644
--- a/include/gdbstub/syscalls.h
+++ b/include/gdbstub/syscalls.h
@@ -22,6 +22,7 @@
 #define GDB_EPERM           1
 #define GDB_ENOENT          2
 #define GDB_EINTR           4
+#define GDB_EIO             5
 #define GDB_EBADF           9
 #define GDB_EACCES         13
 #define GDB_EFAULT         14
@@ -37,6 +38,7 @@
 #define GDB_ENOSPC         28
 #define GDB_ESPIPE         29
 #define GDB_EROFS          30
+#define GDB_ENOSYS         88
 #define GDB_ENAMETOOLONG   91
 #define GDB_EUNKNOWN       9999