--- gcc-16.1.0/gcc/config/ia64/ia64.cc.vanilla	2026-07-31 20:38:25.672523602 +0200
+++ gcc-16.1.0/gcc/config/ia64/ia64.cc	2026-07-31 20:38:25.669109361 +0200
@@ -6179,7 +6179,10 @@ ia64_option_override (void)
 static void
 ia64_override_options_after_change (void)
 {
-  if (optimize >= 3
+  /* Do not enable the selective scheduler by default at -O3: sel-sched
+     corrupts the heap on ia64 (double free / segfault inside
+     run_selective_scheduling, reached from ia64_reorg) on some inputs.  */
+  if (0
       && !OPTION_SET_P (flag_selective_scheduling)
       && !OPTION_SET_P (flag_selective_scheduling2))
     {