In commit 0c727b90 (install(EXPORT): Force absolute paths for usr-move,
2013-03-08) and commit d4774140 (configure_package_config_file: force
absolute paths for usr-move, 2013-01-24) we supported Linux
distributions implementing the "/usr move" by assuming that installation
to (/usr)?/lib(64)? represents a non-relocatable system package.
When cross-compiling one may prepare a package for installation into a
system location on a target machine but install the package files on the
*host* machine inside another path for use with CMAKE_FIND_ROOT_PATH.
In this case the package development files must still be relocatable.
Handle "/usr move" with a new approach that works with relocatable
files. Teach configure_package_config_file and install(EXPORT) to
generate special logic in a package configuration file or targets file
for installation under (/usr)?/lib(64)?. Teach the file to recognize
when it is loaded through a symlink that refers to the same realpath as
its original install destination. In such a case, use the original
install prefix. Otherwise, compute the prefix relative to the current
file location to make it relocatable.
The configure_package_config()_file() macro will now use
absolute paths for the PATH_VARS if the Config.cmake file
will be installed into /lib(64) or /usr/lib(64), since due to
the usr-move filesystem changes Config.cmake files installed
there may be found via two paths (once per symlink via
/lib(64) and once via /usr/lib ), and in this case
relative paths break.
Alex
CONFIGURE_PACKAGE_CONFIG_FILE() now additionally generates
"Any changes to this file will be overwritten by the next CMake run
The input file was FooConfig.cmake.in"
into the configured file.
Alex
Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the
block. This is no longer the preferred style.
Run the following shell code:
for c in else endif endforeach endfunction endmacro endwhile; do
echo 's/\b'"$c"'\(\s*\)(.\+)/'"$c"'\1()/'
done >convert.sed &&
git ls-files -z -- bootstrap '*.cmake' '*.cmake.in' '*CMakeLists.txt' |
egrep -z -v '^(Utilities/cm|Source/kwsys/)' |
egrep -z -v 'Tests/CMakeTests/While-Endwhile-' |
xargs -0 sed -i -f convert.sed &&
rm convert.sed
As discussed on cmake-developers, this patch adds a macro
check_required_components() to the file configured via
configure_package_config_file(), so for proper handling
of components in Config.cmake files users can simply call
check_required_components(PackageName)
and this will do the right thing.
Alex
The function configure_package_config_file() may be used instead of
configure_file() for generating the Config.cmake files for installation,
they help to make those files relocatable.
Alex