impl Sync for various types that need to be statics.

src/glue.rs

@@ -42,6 +42,7 @@ pub struct ProxyTraps {
     pub getPrototypeOf: Option<unsafe extern "C" fn(*mut JSContext, *mut JSObject, *mut *mut JSObject) -> bool>,
     pub trace: Option<unsafe extern "C" fn(*mut JSTracer, *mut JSObject)>,
 }
+unsafe impl Sync for ProxyTraps {}
 
 pub enum AutoIdVector {}
 

src/jsapi.rs

@@ -319,6 +319,7 @@ pub struct JSClass {
     pub trace: JSTraceOp,
     pub reserved: [*mut c_void; 40u],
 }
+unsafe impl Sync for JSClass {}
 pub struct JSConstDoubleSpec {
     pub dval: c_double,
     pub name: *const c_char,

src/rust.rs

@@ -168,7 +168,7 @@ pub unsafe extern fn reportError(_cx: *mut JSContext, msg: *const c_char, report
     error!("Error at {}:{}: {}\n", fname, lineno, msg);
 }
 
-pub fn with_compartment<R, F: Fn() -> R>(cx: *mut JSContext, object: *mut JSObject, cb: F) -> R {
+pub fn with_compartment<R, F: FnMut() -> R>(cx: *mut JSContext, object: *mut JSObject, mut cb: F) -> R {
     unsafe {
         let call = JS_EnterCrossCompartmentCall(cx, object);
         let result = cb();