diff --git a/src/unix/unix.c b/src/unix/unix.c
index d7db5cbef..f707757fb 100644
--- a/src/unix/unix.c
+++ b/src/unix/unix.c
@@ -374,9 +374,9 @@ void *
 plat_mmap(size_t size, uint8_t executable)
 {
 #if defined __APPLE__ && defined MAP_JIT
-    void *ret = mmap(0, size, PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0), MAP_ANON | MAP_PRIVATE | (executable ? MAP_JIT : 0), 0, 0);
+    void *ret = mmap(0, size, PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0), MAP_ANON | MAP_PRIVATE | (executable ? MAP_JIT : 0), -1, 0);
 #else
-    void *ret = mmap(0, size, PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0), MAP_ANON | MAP_PRIVATE, 0, 0);
+    void *ret = mmap(0, size, PROT_READ | PROT_WRITE | (executable ? PROT_EXEC : 0), MAP_ANON | MAP_PRIVATE, -1, 0);
 #endif
     return (ret < 0) ? NULL : ret;
 }