Index: libco/settings.h
--- libco/settings.h.orig
+++ libco/settings.h
@@ -3,7 +3,7 @@
 /*[amd64, arm, ppc, x86]:
    by default, co_swap_function is marked as a text (code) section
    if not supported, uncomment the below line to use mprotect instead */
-/* #define LIBCO_MPROTECT */
+#define LIBCO_MPROTECT
 
 /*[amd64]:
    Win64 only: provides a substantial speed-up, but will thrash XMM regs
