Generator expressions, including configuration-specific expressions may
be used as link libraries of targets. The old-style keywords of
target_link_libraries are handled in terms of new generator expressions.
However, the generator expressions expect target names to be valid
against a regular expression, whereas target_link_libraries does not
require validation. In generator expression constructed without any
action from the user we need to ensure that only valid expressions are
generated. Ensure that strings which are not valid target names are not
used in generator expressions which validate the argument.
Code like
target_link_libraries(B debug A)
generates usage requirement references such as "$<$<CONFIG:DEBUG>:A>".
When cmTarget::GetIncludeDirectories uses such references it generates
expressions like:
$<TARGET_PROPERTY:$<$<CONFIG:DEBUG>:A>,INTERFACE_INCLUDE_DIRECTORIES>
When the conditions are false such references evaluate as an empty
string and the expression fails with an error such as:
$<TARGET_PROPERTY:tgt,prop> expression requires a non-empty target name.
Fix this by teaching cmTarget::GetIncludeDirectories to wrap the above
expression inside a conditional:
$<$<BOOL:$<$<CONFIG:DEBUG>:A>>:...>
so that $<TARGET_PROPERTY:...> will not be evaluated with an empty
target.
Maintain a target's internal list of usage requirement include
directories whenever the LINK_LIBRARIES property is set by either
target_link_libraries or set_property.
In commit 236133e7 (Handle targets in the LINK_LIBRARIES of try_compile,
2013-02-09) an error return case was added without closing the file in
progress. Add the missing fclose() call.
Spotted by sevenhill.
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.
In VS IDE generators add a pre-build event to perform automoc instead of
using a separate custom target. This reduces the number of targets in the
.sln that need to be loaded by the IDE.
This also works around a VS 11 bug as discussed in issue 13900.
Suggested-by: Hauke Heibel <hauke.heibel@gmail.com>
When called with a non-existent LHS target name the user may be trying
to add file-level dependencies. Clarify the error message to explain
the difference between target-level and file-level dependencies. Point
the reader at the commands and options needed for the latter.
We can do this check only if the TargetName is non-empty, which means
that we're evaluating INTERFACE_INCLUDE_DIRECTORIES from a linked
dependency which was set using target_link_libraries.
It is possible to have relative paths in INCLUDE_DIRECTORIES already
in CMake 2.8.10.2, so that part will require a policy to fix.
