diff --git a/lib/emscripten/src/syscalls/mod.rs b/lib/emscripten/src/syscalls/mod.rs
index 58ee32b07..8c1b0a43a 100644
--- a/lib/emscripten/src/syscalls/mod.rs
+++ b/lib/emscripten/src/syscalls/mod.rs
@@ -24,7 +24,6 @@ use libc::{
     close,
     dup2,
     exit,
-    fcntl,
     fstat,
     getpid,
     // readlink,
@@ -596,25 +595,6 @@ pub fn ___syscall218(_ctx: &mut Ctx, _one: i32, _two: i32) -> i32 {
     -1
 }
 
-// fcntl64
-pub fn ___syscall221(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> c_int {
-    debug!("emscripten::___syscall221 (fcntl64) {}", _which);
-    // fcntl64
-    let fd: i32 = varargs.get(ctx);
-    let cmd: i32 = varargs.get(ctx);
-    let arg: i32 = varargs.get(ctx);
-    // (FAPPEND   - 0x08
-    // |FASYNC    - 0x40
-    // |FFSYNC    - 0x80
-    // |FNONBLOCK - 0x04
-    let ret = unsafe { fcntl(fd, cmd, arg) };
-    debug!("=> fd: {}, cmd: {} = {}", fd, cmd, ret);
-    if ret == -1 {
-        debug!("=> last os error: {}", Error::last_os_error(),);
-    }
-    ret
-}
-
 pub fn ___syscall268(_ctx: &mut Ctx, _one: i32, _two: i32) -> i32 {
     debug!("emscripten::___syscall268");
     -1
diff --git a/lib/emscripten/src/syscalls/unix.rs b/lib/emscripten/src/syscalls/unix.rs
index 4a4b98cae..6a0b4d988 100644
--- a/lib/emscripten/src/syscalls/unix.rs
+++ b/lib/emscripten/src/syscalls/unix.rs
@@ -1076,6 +1076,24 @@ pub fn ___syscall220(ctx: &mut Ctx, _which: i32, mut varargs: VarArgs) -> i32 {
     pos as i32
 }
 
+// fcntl64
+pub fn ___syscall221(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> c_int {
+    debug!("emscripten::___syscall221 (fcntl64) {}", _which);
+    let fd: i32 = varargs.get(ctx);
+    let cmd: i32 = varargs.get(ctx);
+    let arg: i32 = varargs.get(ctx);
+    // (FAPPEND   - 0x08
+    // |FASYNC    - 0x40
+    // |FFSYNC    - 0x80
+    // |FNONBLOCK - 0x04
+    let ret = unsafe { fcntl(fd, cmd, arg) };
+    debug!("=> fd: {}, cmd: {} = {}", fd, cmd, ret);
+    if ret == -1 {
+        debug!("=> last os error: {}", Error::last_os_error(),);
+    }
+    ret
+}
+
 /// fallocate
 pub fn ___syscall324(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> c_int {
     debug!("emscripten::___syscall324 (fallocate) {}", _which);
diff --git a/lib/emscripten/src/syscalls/windows.rs b/lib/emscripten/src/syscalls/windows.rs
index 296d51814..a04a978d2 100644
--- a/lib/emscripten/src/syscalls/windows.rs
+++ b/lib/emscripten/src/syscalls/windows.rs
@@ -291,6 +291,12 @@ pub fn ___syscall220(_ctx: &mut Ctx, _one: i32, _two: i32) -> i32 {
     -1
 }
 
+// fcntl64
+pub fn ___syscall221(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> c_int {
+    debug!("emscripten::___syscall221 (fcntl64) {}", _which);
+    -1
+}
+
 /// fchown
 pub fn ___syscall207(_ctx: &mut Ctx, _which: c_int, _varargs: VarArgs) -> c_int {
     debug!("emscripten::___syscall207 (fchown) {}", _which);