diff --git a/cmdgen.c b/cmdgen.c
index 610a8c4a..fe083a0c 100644
--- a/cmdgen.c
+++ b/cmdgen.c
@@ -126,6 +126,10 @@ char *x_get_default(const char *key)
 void sk_cleanup(void)
 {
 }
+void queue_idempotent_callback(IdempotentCallback *ic)
+{
+    assert(0);
+}
 
 void showversion(void)
 {
diff --git a/misc.c b/misc.c
index 42a4a228..efb83579 100644
--- a/misc.c
+++ b/misc.c
@@ -707,6 +707,7 @@ void bufchain_init(bufchain *ch)
 {
     ch->head = ch->tail = NULL;
     ch->buffersize = 0;
+    ch->ic = NULL;
 }
 
 void bufchain_clear(bufchain *ch)
@@ -758,6 +759,9 @@ void bufchain_add(bufchain *ch, const void *data, int len)
 	    ch->tail = newbuf;
 	}
     }
+
+    if (ch->ic)
+        queue_idempotent_callback(ch->ic);
 }
 
 void bufchain_consume(bufchain *ch, int len)
diff --git a/misc.h b/misc.h
index b63df049..0977050b 100644
--- a/misc.h
+++ b/misc.h
@@ -78,6 +78,7 @@ struct bufchain_granule;
 struct bufchain_tag {
     struct bufchain_granule *head, *tail;
     int buffersize;		       /* current amount of buffered data */
+    IdempotentCallback *ic;
 };
 
 void bufchain_init(bufchain *ch);
diff --git a/testbn.c b/testbn.c
index 16529e27..0abe4690 100644
--- a/testbn.c
+++ b/testbn.c
@@ -33,6 +33,7 @@ int random_byte(void)
 }
 
 void logevent(Frontend *frontend, const char *msg) { assert(0); }
+void queue_idempotent_callback(IdempotentCallback *ic) { assert(0); }
 
 #define fromxdigit(c) ( (c)>'9' ? ((c)&0xDF) - 'A' + 10 : (c) - '0' )
 
diff --git a/windows/winpgen.c b/windows/winpgen.c
index d951fa6b..ecb28ac4 100644
--- a/windows/winpgen.c
+++ b/windows/winpgen.c
@@ -60,8 +60,9 @@ void nonfatal(const char *fmt, ...)
     sfree(stuff);
 }
 
-/* Stub needed to link against misc.c */
+/* Stubs needed to link against misc.c */
 void logevent(Frontend *frontend, const char *msg) { assert(0); }
+void queue_idempotent_callback(IdempotentCallback *ic) { assert(0); }
 
 /* ----------------------------------------------------------------------
  * Progress report code. This is really horrible :-)
diff --git a/windows/winpgnt.c b/windows/winpgnt.c
index 0f89b810..2fa53654 100644
--- a/windows/winpgnt.c
+++ b/windows/winpgnt.c
@@ -113,8 +113,9 @@ static void unmungestr(char *in, char *out, int outlen)
     return;
 }
 
-/* Stub needed to link against misc.c */
+/* Stubs needed to link against misc.c */
 void logevent(Frontend *frontend, const char *msg) { assert(0); }
+void queue_idempotent_callback(IdempotentCallback *ic) { assert(0); }
 
 static int has_security;