--- gcc-master.orig/gcc/c-family/cppspec.c	2020-06-05 23:56:44.252712675 +0100
+++ gcc-master/gcc/c-family/cppspec.c	2020-06-12 10:01:08.089478845 +0100
@@ -198,3 +198,9 @@
 
 /* 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)
+{
+}
