From 3c593f28ede99b77d4fe3258f9bda78dcee238a3 Mon Sep 17 00:00:00 2001
From: Andrew Aladjev <aladjev.andrew@gmail.com>
Date: Tue, 9 Feb 2021 08:48:03 +0300
Subject: [PATCH] Fixed default coroutine selection for musl.

---
 configure.ac | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index fc6523408b..87a13758f2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2472,7 +2472,10 @@ AS_CASE([$rb_cv_coroutine], [yes|''], [
             rb_cv_coroutine=emscripten
         ],
         [
-            rb_cv_coroutine=ucontext
+            AC_CHECK_FUNCS([getcontext swapcontext makecontext],
+                [rb_cv_coroutine=ucontext],
+                [rb_cv_coroutine=copy; break]
+            )
         ]
     )
     AC_MSG_RESULT(${rb_cv_coroutine})