[Development] About the presence of /System/Library/Frameworks/Carbon.framework

[Edward Welbourne]

René J.V. Bertin:
>>> Here's a silly one: configuring Qt for building on my Linux rig I was told
>>> that I needed Xcode, and how to get it. :)
>>>
>>> Long story short, it turns out that the configure script determines
>>> whether it's building on Mac by checking if the Carbon framework exists
>>> in the designated location. And it turns out that I copied over the
>>> entire header dir. structure under /System/Library/Frameworks onto said
>>> Linux rig because I use it for cross-platform development.
>>>
>>> Apart from the fact that it should probably check for a framework with a
>>> more certain future, isn't there a less "rootsy" way of determining
>>> whether the script is running on Mac?

On quinta-feira, 21 de dezembro de 2017 04:47:34 CST Konstantin Tokarev wrote:
>> Check uname maybe?

Thiago Macieira (21 December 2017 12:54) replied:
> That would tell you the host you're running on, not the target you're
> compiling to.
>
> If your sysroot contains Apple files, it's reasonable to conclude it's an
> Apple system.

Well, it's reasonable to conclude you're set up to be capable of
compiling for an Apple system; as here, it's possible this may be for
the sake of cross-compiling; but the fact of having the means to
cross-compile for a particular target does not mean that every build
done on this machine necessarily is a cross-compile for that target.

It does sound like we're a little too enthusiastic about jumping to a
conclusion here - is there a better way to decide what we're compiling
for ?  Surely we should ignore uname if configure has options that
explicitly ask for cross-compilation; but it's a reasonable thing to
consult otherwise, when auto-detecting in the absence of explicit
instructions - in particular, more to be trusted than the existence of
(possibly non-native) frameworks,

	Eddy.