In commit v3.5.0-rc1~43^2 (Fix export of STATIC library PRIVATE
dependencies with CMP0022 NEW, 2016-01-15) we taught
target_link_libraries to generate `$<LINK_ONLY:$<TARGET_NAME:dep>>` in
INTERFACE_LINK_LIBRARIES instead of `$<LINK_ONLY:dep>` so that `dep` can
be recognized as a target name and updated during export. However, this
approach does not work when `dep` is just a plain library name and not a
target because `$<TARGET_NAME:...>` requires the name of a reachable
target.
Since we do not know during target_link_libraries whether the name will
correspond to a reachable target or not, we cannot inject the
`$<TARGET_NAME:...>` expression. Revert this change and solve the
original problem instead by teaching the export logic to recognize and
update target names directly in `$<LINK_ONLY:...>` expressions.
Reported-by: Ben Boeckel <ben.boeckel@kitware.com>
The change in commit 27252b24 (cmComputeLinkInformation: Simplify
generator object access, 2015-08-02) broke the conditional use of a
target introduced in commit 41abdc17 (cmGeneratorTarget: Move GetSOName
from cmTarget, 2015-08-04). Restore the conditional lookup. Add a test
case that hacks platform information variables to trigger this code
everywhere.
Since commit v3.3.0-rc1~62^2~5 (cmTarget: Store only cmListFileContext
for CMP0023 handling, 2015-05-18) a call to target_link_libraries on a
target that was defined in another (non-ancestor) directory crashes
because no execution context is left active. Fix this by getting the
execution context from the actual cmMakefile where the current
target_link_libraries call takes place. Test this by verifying that
such calls correctly produce an error diagnostic instead of crashing.
Add a new signature to help populate INTERFACE_LINK_LIBRARIES and
LINK_LIBRARIES cleanly in a single call. Add policy CMP0023 to control
whether the keyword signatures can be mixed with uses of the plain
signatures on the same target.
Brad King
Stephen Kelly