XCODE_LINK_BUILD_PHASE_MODE KNOWN_LOCATION moves non-target library
items with a known path into the "Link Binary With Libraries" build
phase, requiring a valid PBXFileReference. Framework items specified
without a directory component (e.g. $<LINK_LIBRARY:FRAMEWORK,Foundation>)
are stored as ItemIsPath::Yes in cmComputeLinkInformation, but their
value is just a bare name. This caused CreateXCodeFileReferenceFromPath
to CollapseFullPath the bare name against the current working directory,
producing a broken reference to a non-existent path that Xcode shows
as a missing file, and that results in failure to link the project.
We now check that a non-target framework item has a non-empty directory
component before allowing it into the link phase. Without a concrete
path we can't produce a valid PBXFileReference, so we fall back to
OTHER_LDFLAGS where the item is already correctly formatted as
-framework Name.
For policy-specific tests, use the version before the policy was
introduced. Otherwise, use 3.5 where possible.
Also, remove `cmake_minimum_required()` and `project()` calls from
individual cases where they are handled by `CMakeLists.txt`.
OBJECT and STATIC libraries (framework or non-framework) do not use
this build phase. Not all items to be linked use this build phase either.
Co-Authored-By: Craig Scott <craig.scott@crascit.com>
Tor Arne Vestbø
Brad King
Marc Chevrier
Gusts Kaksis
