[CMake] xcode project and static library dependencies

[Bill Hoffman]

>> I have changes that cause cmake to produce an Xcode project in which the
>> targets do not have the extra phases, and the dependencies are set up such
>> that incremental builds work efficiently!
>>
>> But I'm having some impedance mismatches between where Xcode want the
>> build results to be and where cmake wants them.  Xcode (like many makefiles)
>> has the concept of a normal build and an "install" build.  But when cmake
>> runs it builds some test programs using the xcodebuild command line, but
>> does not specify the "install" action but then expects to find the resulting
>> executable in the install location.
>>
>> I'm sure I could change TryCompileCode() to add "install" to the
>> xcodebuild line, but it seems like lots of other cmake scripts will have the
>> same expectations.  I playing with trying to get Xcode to always do an
>> "install".  I tried creating xcode projects with the initial (not install)
>> locations being where cmake wants them, but xcode seems to not do the
>> internal dependency analysis properly when the intermediate results are not
>> within BUILD_PRODUCTS_DIR.
>>
>> What is the cmake model for where the results of a build go?
>
> Putting the results where the native tool expects them is fine. CMake makes
> no guarantees about where build products go. If a native tool has no
> expectations, we try to hide build results underneath the "CMakeFiles/"
> directories in the build tree to avoid cluttering a developer's view of the
> build tree with stuff they mostly don't need to see...
> I don't think there are any hard requirements w.r.t. build products
> locations. Although where libraries and executables end up is important for
> the CMake generated install rules to work.
> Feel free to change things around experimentally if that makes it easy to
> work with newer Xcode versions. The test suite will very likely tell us if
> things have gone awry.
>

That is not entirely true....

Things like EXECUTABLE_OUTPUT_PATH and target location properties have
to work without an extra install step. What do you mean CMake expects
to find things in install locations?  CMake does need to be able to
find executables after the build is run.  It also needs to be able to
place them via location properties.

-Bill