Help: Add notes about relocatability of config-file packages.

This commit is contained in:
Stephen Kelly 2014-01-07 18:15:27 +01:00
parent beb9cfae17
commit bb8bde35b8
1 changed files with 34 additions and 4 deletions

View File

@ -392,11 +392,41 @@ should be provided by the ``ClimbingStats`` package, they should
be in a separate file which is installed to the same location as the
``ClimbingStatsConfig.cmake`` file, and included from there.
Packages created by :command:`install(EXPORT)` are designed to be relocatable,
using paths relative to the location of the package itself. When defining
the interface of a target for ``EXPORT``, keep in mind that the include
directories should be specified as relative paths which are relative to the
:variable:`CMAKE_INSTALL_PREFIX`:
.. code-block:: cmake
target_include_directories(tgt INTERFACE
# Wrong, not relocatable:
$<INSTALL_INTERFACE:${CMAKE_INSTALL_PREFIX}/include/TgtName>
)
target_include_directories(tgt INTERFACE
# Ok, relocatable:
$<INSTALL_INTERFACE:include/TgtName>
)
The ``$<INSTALL_PREFIX>``
:manual:`generator expression <cmake-generator-expressions(7)>` may be used as
a placeholder for the install prefix without resulting in a non-relocatable
package. This is necessary if complex generator expressions are used:
.. code-block:: cmake
target_include_directories(tgt INTERFACE
# Ok, relocatable:
$<INSTALL_INTERFACE:$<$<CONFIG:Debug>:$<INSTALL_PREFIX>/include/TgtName>>
)
The :command:`export(EXPORT)` command creates an :prop_tgt:`IMPORTED` targets
definition file which is specific to the build-tree. This can similiarly be
used with a suitable package configuration file and package version file to
define a package for the build tree which may be used without installation.
Consumers of the build tree can simply ensure that the
definition file which is specific to the build-tree, and is not relocatable.
This can similiarly be used with a suitable package configuration file and
package version file to define a package for the build tree which may be used
without installation. Consumers of the build tree can simply ensure that the
:variable:`CMAKE_PREFIX_PATH` contains the build directory, or set the
``ClimbingStats_DIR`` to ``<build_dir>/ClimbingStats`` in the cache.