Firefox build issues with Rust and the new VS2017 15.5 update

Ryan VanderMeulen rvandermeulen at
Tue Dec 5 16:16:24 UTC 2017

FYI, the VC++ 2017 v14.12 toolset included in the recently-released VS2017
15.5 update appears to have broken building Firefox due to issues with the
Rust compiler (in particular, the version of libclang we ship with it) and
one of the system headers:

error: '_Ty' does not refer to a value

Which in turns leads to a Rust panic and build failure.

The Visual Studio installer allows you to install the prior v14.11 toolset
as well, but I haven't verified yet that our build system will properly use
it if it's there. In the mean time, I'd strongly advise avoiding this
update until it's sorted out.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the firefox-dev mailing list