diff --git a/Makefile.am b/Makefile.am
index eed4735..4a63875 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4,6 +4,7 @@ glorytun_LDADD = $(libsodium_LIBS)
 glorytun_SOURCES = \
     src/common.h \
     src/common-static.h \
+    src/common.c \
     src/ip-static.h \
     src/main.c \
     src/option.c \
diff --git a/src/common.c b/src/common.c
new file mode 100644
index 0000000..ea84c7a
--- /dev/null
+++ b/src/common.c
@@ -0,0 +1,8 @@
+#include "common.h"
+
+#include <stdio.h>
+
+void gt_not_available (const char *name)
+{
+    fprintf(stderr, "%s is not available on your platform!\n", name);
+}
diff --git a/src/common.h b/src/common.h
index 4a0477c..d3c690d 100644
--- a/src/common.h
+++ b/src/common.h
@@ -24,3 +24,5 @@ struct buffer {
     uint8_t *write;
     uint8_t *end;
 };
+
+void gt_not_available (const char *);
diff --git a/src/main.c b/src/main.c
index 88bd0c4..3d43317 100644
--- a/src/main.c
+++ b/src/main.c
@@ -43,11 +43,6 @@ struct crypto_ctx {
 
 volatile sig_atomic_t running;
 
-static void gt_not_available (const char *name)
-{
-    fprintf(stderr, "%s is not available on your platform!\n", name);
-}
-
 static int64_t dt_ms (struct timeval *ta, struct timeval *tb)
 {
     const int64_t s = ta->tv_sec-tb->tv_sec;