Workaround found here:
https://bugs.cpan.org/Public/Bug/Display.html?id=37451

--- src/if_perl.xs	2016-05-19 11:00:51.372810668 +0200
+++ src/if_perl.xs	2016-05-19 14:02:08.000000000 +0200
@@ -49,6 +49,17 @@
 # define __inline__ __inline
 #endif
 
+/* Work around for perl < 5.8.7 */
+#ifndef PERLIO_FUNCS_DECL
+#  ifdef PERLIO_FUNCS_CONST
+#    define PERLIO_FUNCS_DECL(funcs) const PerlIO_funcs funcs
+#    define PERLIO_FUNCS_CAST(funcs) (PerlIO_funcs*)(funcs)
+#  else
+#    define PERLIO_FUNCS_DECL(funcs) PerlIO_funcs funcs
+#    define PERLIO_FUNCS_CAST(funcs) (funcs)
+#  endif
+#endif /* PERLIO_FUNCS_DECL */
+
 #ifdef __GNUC__
 # pragma GCC diagnostic push
 # pragma GCC diagnostic ignored "-Wunused-variable"