Building with clang needs --clang=1

[springmeyer]

You need to pass --clang=1 to avoid these flags being set, which - with recent versions of clang - cause the compile to stop abruptly.

Ideally node-gyp would handle this automatically, but its not the case so this workaround is needed.

TODO: document this in the node-pre-gyp readme or a GOCHAS page or maybe automatically handle it in node-pre-gyp?

[springmeyer]

node core has handled this now upstream. It was only an issue with v0.x series.