[Development] OS X SDK set via configure is not used during build (dev branch)

[Mikkel Krautz]

Hi,

I'm currently on 10.10, Yosemite, using Xcode 7.1.1 (as of this writing).

This version of Xcode only ships with the 10.11 SDK. But I am on 10.10.

When I built Qt (dev branch), by passing -sdk macosx10.11 -- the only
SDK I have -- to configure, I get build failures.

Inspecting the compiler flags, I see that the OS X 10.10 SDK is being
used (-isysroot, etc.).

It seems to be because qtbase/mkspecs/common/macx.conf sets
QMAKE_MAC_SDK to "macosx".

As a quick local fix, I set this to "macosx10.11", and I could
correctly build Qt again.

I don't think this is a configuration error on my end, or a bug in Xcode.
For example, xcodebuild correctly translates the non-versioned "macosx" SDK to
"macosx10.11".

$ xcodebuild -sdk macosx

Build settings from command line:

    SDKROOT = macosx10.11

[...]

Does anyone know what's going on?

Thanks,
Mikkel