diff --git a/client/util.c b/client/util.c
index 1d83e518..3a78a7c4 100644
--- a/client/util.c
+++ b/client/util.c
@@ -17,7 +17,7 @@
 /* Client versions of logging functions */
 
 static void
-vlog(const char *msg, va_list args)
+vlog_cli(const char *msg, va_list args)
 {
   char buf[1024];
 
@@ -38,7 +38,7 @@ bug(const char *msg, ...)
   va_start(args, msg);
   cleanup();
   fputs("Internal error: ", stderr);
-  vlog(msg, args);
+  vlog_cli(msg, args);
   vfprintf(stderr, msg, args);
   va_end(args);
   exit(1);
@@ -51,7 +51,7 @@ die(const char *msg, ...)
 
   va_start(args, msg);
   cleanup();
-  vlog(msg, args);
+  vlog_cli(msg, args);
   va_end(args);
   exit(1);
 }
diff --git a/lib/birdlib.h b/lib/birdlib.h
index 57149cc9..41aa8b3f 100644
--- a/lib/birdlib.h
+++ b/lib/birdlib.h
@@ -16,6 +16,8 @@
 #include "lib/alloca.h"
 #include "lib/macro.h"
 
+#include <stdarg.h>
+
 /* Ugly structure offset handling macros */
 
 #define SAME_TYPE(a, b)	({ int _ = ((a) != (b)); !_; })
@@ -211,6 +213,7 @@ void log_msg(const char *msg, ...);
 void log_rl(struct tbf *rl, const char *msg, ...);
 void die(const char *msg, ...) NORET;
 void bug(const char *msg, ...) NORET;
+void vlog(int class, const char *msg, va_list args);
 
 #define L_DEBUG "\001"			/* Debugging messages */
 #define L_TRACE "\002"			/* Protocol tracing */
diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 9d77211b..384da303 100644
--- a/sysdep/unix/log.c
+++ b/sysdep/unix/log.c
@@ -337,7 +337,7 @@ log_prepare(log_buffer *buf, int class)
   buf->pos[LBP_MSG] = buf->buf.pos;
 }
 
-static void
+void
 vlog(int class, const char *msg, va_list args)
 {
   static _Thread_local log_buffer buf;