Replace calls to GetLinkInformation with calls to a method to get only
the target closure, not the link languages etc. The replaced calls
are used while evaluating generator expressions only. This makes
transitive generator expression evaluation independent from
the languages of a target. In a follow-up topic, it will be possible
to make the languages depend on generator expression evaluation, via
evaluation of the SOURCES and INTERFACE_SOURCES target properties.
Because the order of entries is not the same as the final link line,
the order of debug output is different in the RunCMake.CompatibleInterface
test, because the BOOL_PROP7 target property is evaluated first. Adjust
the test to account for that new order.
For the OLD CMP0022 behavior, we need to treat the implementation
as the interface when computing the interface libraries. Make it
possible to do that without computing the link languages by adding
a new GetLinkImplementationLibraries method. Extend the existing
GetLinkImplementation method to populate the languages if the
libraries have already been computed and cached.
Change GetTransitivePropertyTargets to invoke GetLinkInterfaceLibraries
instead of GetLinkInterface. This is key, as it is a method called
by cmGeneratorExpressionEvaluator.
Change the cmGeneratorExpressionEvaluator to invoke
GetLinkImplementationLibraries instead of GetLinkImplementation.
When evaluating the SOURCES property, we will need to be able to access
the link libraries without accessing the link languages, as the languages
depend on the SOURCES.
Arrange the logic so that the part which deals with libraries only is
at the top. In a follow-up commit, this will be split into two methods.
Ensure that the explanatory CMP0022 comment is only present in one
location.
The callers already skip non-targets, so unify the target search.
Change supporting functions to accept a container of targets instead
of strings where possible.
In a follow-up, the list of sources will become dependent on
the config, so check for existence in cmTarget::GetSourceFiles
instead of up-front with cmGlobalGenerator::CheckTargets().
Historically CMake used three version components for the feature level.
We released new features while incrementing only the third version
component. Since commit v2.8.2~105^2~4 (New version scheme to support
branchy workflow, 2010-04-23) we used the fourth version component for
bug-fix releases and the development date:
<major>.<minor>.<patch>[.<tweak>][-rc<n>] = Release
<major>.<minor>.<patch>.<date>[-<id>] = Development
This solidified use of three components for the feature level, and was
necessary to continue releasing 2.x versions because:
* Some existing projects performed floating-point comparisons of
${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} to 2.x numbers
so ``x`` could never be higher than 9.
* Version 2.9.<date> was used briefly in post-2.8.0 development in
CVS prior to the transition to Git, so using it in releases may
have caused confusion.
Now that we are moving to 3.x versions, these two restrictions go away.
Therefore we now change to use only two components for the feature
level and use the scheme:
<major>.<minor>.<patch>[-rc<n>] = Release
<major>.<minor>.<date>[-<id>] = Development
People will be tempted to put things there for convenience, thereby
causing conflicts similar to
http://thread.gmane.org/gmane.comp.compilers.clang.devel/35162/focus=35169
where it is conceivable that the LLVM developers could put a flag on
a target for convenience, which would cause conflicts for some downstreams.
When building boost with an alternate namespace the libraries generated
will have a different naming convention. This is often done to ensure
no symbol conflicts with external libraries built against a different
version of boost. If the namespace used is "myprivateboost::" instead
of "boost::" then the libraries built will be named myprivateboost_foo
instead of boost_foo. Add an option to specify a custom namespace used
to alter the library names that get searched for.
The cmGeneratorExpression is used here, but the header for it is not
in the include heirarchy. This would be a compile error if the file
were compiled as a standalone translation unit, but it is instead
used in a mini-unity-build by inclusion in cmCommands.cxx. The header
for cmGeneratorExpression happens to be included first, so the
compilation works fine.
IDEs do not know this however, and flag the use as an error.
