diff --git a/signal.c b/signal.c
index 7d2226b766..238679e1bd 100644
--- a/signal.c
+++ b/signal.c
@@ -1588,7 +1588,7 @@ fake_grantfd(int masterfd)
     errno = ENOSYS;
     return -1;
 }
-#define grantpt(fd) fake_grantfd(int)
+#define grantpt(fd) fake_grantfd(fd)
 #endif
 
 int