diff --git a/vcs-svn/fast_export.c b/vcs-svn/fast_export.c
index 2e5bb67255..99ed70b88a 100644
--- a/vcs-svn/fast_export.c
+++ b/vcs-svn/fast_export.c
@@ -51,7 +51,8 @@ void fast_export_commit(uint32_t revision, const char *author,
 		   *author ? author : "nobody",
 		   *author ? author : "nobody",
 		   *uuid ? uuid : "local", timestamp);
-	printf("data %"PRIuMAX"\n", log->len + strlen(gitsvnline));
+	printf("data %"PRIuMAX"\n",
+		(uintmax_t) (log->len + strlen(gitsvnline)));
 	fwrite(log->buf, log->len, 1, stdout);
 	printf("%s\n", gitsvnline);
 	if (!first_commit_done) {