building servo on ubuntu 16.04 fails at mozjs

[paddywwoof]

not clear how this error can be fixed without altering the source.

   Compiling mozjs v0.8.0                                                       
error[E0277]: the trait bound `u8: std::convert::From<rust::MutableHandle<'_, u8>>` is not satisfied
    -->.../mozjs-0.8.0/src/rust.rs:1205:52
     |
1205 |             wrap!(@inner $saved <> ($($acc,)* $arg.into(),) <> $($rest)*);
     |                                                    ^^^^ the trait `std::convert::From<rust::MutableHandle<'_, u8>>` is not implemented for `u8`
     | 
    ::: .../mozjs-0.8.0/src/jsapi_wrappers.in:44:1
     |
44   | wrap!(jsapi: pub fn FinishMultiOffThreadScriptsDecoder(cx: *mut JSContext, token: *mut ::std::os::raw::c_void, scripts: MutableHandle<ScriptVector>) -> bool);
     | -------------------------------------------------------------------------------------------------------------------------------------------------------------- in this macro invocation
     |
     = help: the following implementations were found:
               <u8 as std::convert::From<bool>>
     = note: required because of the requirements on the impl of `std::convert::Into<u8>` for `rust::MutableHandle<'_, u8>`

error[E0277]: the trait bound `u8: std::convert::From<rust::MutableHandle<'_, u8>>` is not satisfied
    --> .../mozjs-0.8.0/src/rust.rs:1348:113
     |
1348 |             wrap!(@inner $saved <> ($($declargs)* $arg: &mut MutableHandle<$gentype> , )  <> ($($acc,)* (*$arg).into(),) <> $($rest)*);
     |                                                                                                                 ^^^^ the trait `std::convert::From<rust::MutableHandle<'_, u8>>` is not implemented for `u8`
     | 
    .../mozjs-0.8.0/src/jsapi_wrappers.in:44:1

[jdm]

This is caused by a too-old version of llvm being used for libclang. Replacing it with a newer version should make it go away.

[jdm]

Oh, this may be caused by a version of clang that is less than 3.9.

[rohit-136]

@jdm
I updated my clang version to version 6 but it still shows the same error.

[jdm]

@rohit-136 In general, that means that you have an older version of clang that is being found before the updated version.

[rohit-136]

@jdm I uninstalled clang 3.8 just to be sure and installed clang 6.0.1. The error persists even then.