$OpenBSD$

Index: utf8.c
--- utf8.c.orig
+++ utf8.c
@@ -23,9 +23,9 @@
 #include <malloc.h>
 #define snprintf _snprintf
 #else
-#ifndef __FreeBSD__
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__)
 #include <alloca.h>
-#endif /* __FreeBSD__ */
+#endif /* !__FreeBSD__ && !__OpenBSD__ */
 #endif
 #include <assert.h>
 
