This introduces the unset() command to make it easy to unset CMake
variables, environment variables, and CMake cache variables. Previously
it was not even possible to unset ENV or CACHE variables (as in
completely remove them). Changes based on patch from Philip Lowman.
See issue #7507.
Some native build tools, particularly those for cross compiling, may
have a limit on the length of the full path to an object file name that
is lower than the platform otherwise supports. This change allows the
limit to be set by the project toolchain file through the variable
CMAKE_OBJECT_PATH_MAX.
It is useful to be able to test if a target has been created. Often
targets are created only inside conditions. Rather than storing the
result of the condition manually for testing by other parts of the
project, it is much easier for the other parts to just test for the
target's existence. This will also be useful when find-modules start
reporting results with IMPORTED targets and projects want to test if a
certain target is available.
We frequently need to wipe out all the CMake test build directories in
order to run tests from scratch. This change adds a test_clean custom
target to remove all these directories for out-of-source builds.
When creating an IMPORTED target for a library that has been found on
disk, it may not be known whether the library is STATIC or SHARED.
However, the library may still be linked using the file found from disk.
Use of an IMPORTED target is still important to allow per-configuration
files to be specified for the library.
This change creates an UNKNOWN type for IMPORTED library targets. The
IMPORTED_LOCATION property (and its per-config equivalents) specifies
the location of the library. CMake makes no assumptions about the
library that cannot be inferred from the file on disk. This will help
projects and find-modules import targets found on disk or specified by
the user.
Rename the recently added INTERFACE mode of the target_link_libraries()
command to LINK_INTERFACE_LIBRARIES. This makes it much more distinct
from a normal call to the command, and clearly states its connection to
the property of the same name. Also require the option to appear
immediately after the target name to make it a mode rather than an
option.
It is likely that projects or CMake modules in the future will need to
check the value of a policy setting. For example, if we add a policy
that affects the results of FindXYZ.cmake modules, the module code will
need to be able to check the policy.
A recent change fixed a case in which CMake incorrectly diagnosed a
circular dependency involving a non-linkable executable target. This
adds a test for that case.
As of CMake 2.6 a custom command output specified by relative path is
placed in the build tree. This adds a test to make sure other
references to the output are hooked up correctly, fixing a bug in CMake
2.6.1.
- Previously the find_* commands did not normalize the search paths
- The recent refactoring enabled such normalization
- The FindBase test must also normalize before comparing paths
- Option was recently added but never released.
- Custom commands no longer depend on build.make so we do
not need the option.
- Rule hashes now take care of rebuilding when rules change
so the dependency is not needed.
- Tests IMPLICIT_DEPENDS_INCLUDE_TRANSFORM properties.
- See issue #6648.
- Works without help in VS IDEs due to native dependency handling.
- Xcode needs help to rebuild correctly.
- Allows make rules to be created with no dependencies.
- Such rules will not re-run even if the commands themselves change.
- Useful to create rules that run only if the output is missing.