diff --git a/lib/curl_setup.h b/lib/curl_setup.h
index 4e2540504..799d5fab9 100644
--- a/lib/curl_setup.h
+++ b/lib/curl_setup.h
@@ -217,7 +217,7 @@
 
 /*
  * Use getaddrinfo to resolve the IPv4 address literal. If the current network
- * interface doesn’t support IPv4, but supports IPv6, NAT64, and DNS64,
+ * interface doesn't support IPv4, but supports IPv6, NAT64, and DNS64,
  * performing this task will result in a synthesized IPv6 address.
  */
 #ifdef  __APPLE__