From 95e337f815b68b50d4455c4c9a8722b8794bfffa Mon Sep 17 00:00:00 2001
From: Alan Wu <XrXr@users.noreply.github.com>
Date: Fri, 15 Oct 2021 17:15:42 -0400
Subject: [PATCH] Warn when trying to use YJIT in --disable-jit-support builds

---
 ruby.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/ruby.c b/ruby.c
index f3c01bef0d..5f756ebbc8 100644
--- a/ruby.c
+++ b/ruby.c
@@ -1505,7 +1505,11 @@ proc_options(long argc, char **argv, ruby_cmdline_options_t *opt, int envopt)
 #endif
             }
             else if (strcmp("yjit", s) == 0 || setup_yjit_options(s, &opt->yjit)) {
+#if USE_MJIT
                 FEATURE_SET(opt->features, FEATURE_BIT(yjit));
+#else
+                rb_warn("Ruby was built without JIT support");
+#endif
             }
 	    else if (strcmp("yydebug", s) == 0) {
 		if (envopt) goto noenvopt_long;