--- guile-2.2.0/libguile/gc.h	2018-10-04 01:57:58 +0000
+++ guile-2.2.0/libguile/gc.h_orig	2018-10-04 01:49:00 +0000
@@ -216,6 +216,7 @@
 #ifdef __GNUC__
   __asm__ volatile ("" : : : "memory");
 #else
+SCM_API void scm_remember_upto_here_1 (SCM obj);
   /* portable version, just in case any other compiler does the same
      thing.  */
   scm_remember_upto_here_1 (z);