Fix some compilation errors on MacOS due to an old SDK

[amontoison]

#94

[cvanaret]

Thanks @amontoison!
The command rm -rf /opt/${target}/${target}/sys-root/System in the x86_64-apple-darwin14 build fails:

[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Printers/Libraries': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/Tcl.framework/Versions/8.4/Headers/tcl-private': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/Tcl.framework/Versions/8.5/Headers/tcl-private': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/ForceFeedback.framework/Versions/A/Modules': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/ForceFeedback.framework/Versions/A/Headers': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/QTKit.framework/Versions/A/Modules': I/O error
[18:02:50] rm: can't remove '/opt/x86_64-apple-darwin14/x86_64-apple-darwin14/sys-root/System/Library/Frameworks/QTKit.framework/Versions/A/Headers': I/O error
...

[amontoison]

Where do you have this error?
Is it in a CI build?

[cvanaret]

I retagged to trigger the release build. Perhaps too soon?

[amontoison]

It will not work because you have other compilation errors:
#94 (comment)

[cvanaret]

Ah sorry, I overlooked that one. Looks like the good old missing include that no compiler ever complained about (except now).