diff --git a/bin/varnishd/http1/cache_http1_pipe.c b/bin/varnishd/http1/cache_http1_pipe.c
index dd8b9098b3c..e361ba020eb 100644
--- a/bin/varnishd/http1/cache_http1_pipe.c
+++ b/bin/varnishd/http1/cache_http1_pipe.c
@@ -49,7 +49,7 @@ static struct lock pipestat_mtx;
 static int
 rdf(int fd0, int fd1, uint64_t *pcnt)
 {
-	int i, j;
+	ssize_t i, j;
 	char buf[BUFSIZ], *p;
 
 	i = read(fd0, buf, sizeof buf);