--- libinterp/dldfcn/__ode15__.cc
+++ libinterp/dldfcn/__ode15__.cc	2026-06-07 20:35:53.000000000 +0800
@@ -46,6 +46,10 @@
 
 #if defined (HAVE_SUNDIALS)
 
+#  ifndef HAVE_SUNDIALS_SUNCONTEXT
+#    define HAVE_SUNDIALS_SUNCONTEXT
+#  endif
+
 #  if defined (HAVE_NVECTOR_NVECTOR_SERIAL_H)
 #    include <nvector/nvector_serial.h>
 #  endif