--- gcc-5.2.0-orig/gcc/c-family/cppspec.c	2015-01-30 16:15:00.000000000 +0000
+++ gcc-5.2.0/gcc/c-family/cppspec.c	2016-04-11 13:16:18.659000792 +0100
@@ -197,3 +197,9 @@
 
 /* Number of extra output files that lang_specific_pre_link may generate.  */
 int lang_specific_extra_outfiles = 0;  /* Not used for cpp.  */
+
+/* lang_register_spec_functions.  Not used for cpp.  */
+void
+lang_register_spec_functions (void)
+{
+}
