diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index ec77084..d03c6c0 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -2884,7 +2884,10 @@ PyOS_setsig(int sig, PyOS_sighandler_t handler)
     struct sigaction context, ocontext;
     context.sa_handler = handler;
     sigemptyset(&context.sa_mask);
-    context.sa_flags = 0;
+    /* Using SA_ONSTACK is friendlier to other C/C++/Golang-VM code that
+     * extension module or embedding code may use where tiny thread stacks
+     * are used.  https://bugs.python.org/issue43390 */
+    context.sa_flags = SA_ONSTACK;
     if (sigaction(sig, &context, &ocontext) == -1)
         return SIG_ERR;
     return ocontext.sa_handler;