This tracking was added during the development of commit 042ecf04
(Add API to calculate link-interface-dependent bool properties
or error., 2013-01-06), but was never used.
It was not necessary to use the content because what is really
useful in that logic is to determine if a property has been implied
to be null by appearing in a LINK_LIBRARIES genex.
I think the motivating usecase for developing the feature of
keeping track of the targets relevant to a property was that I
thought it would make it possible to allow requiring granular
compatibility of interface properties only for targets which
depended on the interface property. Eg:
add_library(foo ...)
add_library(bar ...)
add_executable(user ...)
# Read the INTERFACE_POSITION_INDEPENDENT_CODE from bar, but not
# from foo:
target_link_libraries(user foo $<$<TARGET_PROPERTY:POSTITION_INDEPENDENT_CODE>:bar>)
This obviously doesn't make sense. We require that INTERFACE
properties are consistent across all linked targets instead.
We need to make sure expressions which evaluate TARGET_PROPERTY:TYPE
multiple times for example get the correct result each time, and
not an empty string instead.
As INTERFACE_COMPILE_DEFINITIONS are now possible, we can have
situations like this:
add_library(foo ...)
add_library(bar ...)
target_link_libraries(foo bar)
target_compile_definitions(bar INTERFACE SOME_DEF)
The INTERFACE_COMPILE_DEFINITIONS of bar determine how foo should be
compiled, and if they change, foo should be rebuilt.
Additionally, as of commit d1446ca7 (Append the COMPILE_DEFINITIONS
from the Makefile to all targets., 2012-09-17), we don't need to
read definitions from the makefile if we read them from the target,
so also de-duplicate the cached info.
The DependInfo for INTERFACE_INCLUDE_DIRECTORIES is already handled
correctly.
Remove the old "nocwd" behavior that attempts to provide the "--help"
output when no working directory is available. The long help output
scrolls the real error message out of typical terminal sizes. Also
execute as little code as possible when no working directory exists.
Since commit 08cb4fa4 (Process generator expressions in the
INCLUDE_DIRECTORIES property., 2012-09-18), it is possible to use
generator expressions with the include_directories command.
As that command can also have a SYSTEM argument, ensure that the
result of using that argument with generator expressions gives a
sane result.
e48d842 Cache context-independent includes on evaluation.
089fe1c Optimize genex evaluation for includes and defines.
179f495 find_package: Reword <package>_NO_INTERFACES documentation
e7b579b Test workaround of bad interface include directories from depends.
77cecb7 Add includes and compile definitions with target_link_libraries.
0b92602 Add the $<LINKED:...> generator expression.
0fa7f69 Add API to check if we're reading a includes or defines property.
2c3654c Add a way to exclude INTERFACE properties from exported targets.
d4297d5 Export targets to a targets file, not a Config file.
df4d2b2 Make it an error for INSTALL_PREFIX to be evaluated.
7ceeba9 Advance more when preprocessing exported strings.
30268b4 Handle reading empty properties defined by the link interface.
The commit 18a3195a ('Keep track of INCLUDE_DIRECTORIES as a vector
of structs.', 2012-11-19) moved the handling of includes from
cmGeneratorTarget to cmTarget, but in the process introduced this
bug.
link.exe has problems with very very long lines in rsp files too.
Use $in_newline instead of $in variable for rspcontent which
separates the arguments with a newline instead of a simple space
and was specially made for this purpose.
Since commit d46d8df0 (Re-implemented cmGeneratedFileStream to look like a
real stream and replace the destination file atomically, 2004-11-03) our
RenameFile implementation tries to deal with MoveFile not replacing
read-only files. In order to avoid the Get/SetFileAttributes pair we used
stat to test for existence of the destination file. This has a race in
which the destination could be created between the test for existence and
the MoveFile call.
Remove the stat call and use GetFileAttributes to detect whether the file
exists. This shortens the race but does not eliminate it. Use a loop to
try multiple times in case we lose the race. While at it, drop Win9x
support and always use MoveFileEx.
Generator expressions whose output depends on the configuration
now record that fact. The GetIncludeDirectories method can use
that result to cache the include directories for later calls.
GetIncludeDirectories is called multiple times for a target
for each configuration, so this should restore performance for
multi-config generators.
While porting boost to use these features, the generation step took
too long (several minutes before I stopped it). The reason was that
the boost libraries form a large interdependent mesh. The libraries
list their dependencies in their INTERFACE such as:
$<LINKED:boost::core>;$<LINKED:boost::config>;$<LINKED:boost::mpl>
As boost::core already depends on the boost::config libraries, that
expression has no impact on the end-content, as it is removed after
the generation step. There is no DAG issue though, so the generator
expression evaluation would fully evaluate them. In the case of the
config library, it also depends on the core library, so all depends
are followed through that again, despite the fact that they've just
been evaluated. After this patch, the evaluation skips libraries if
they have already been seen via depends or directly in the content.
This patch keeps track of targets whose INTERFACE has been consumed
already. The INCLUDE_DIRECTORIES and COMPILE_DEFINITIONS properties
are whitelisted because repeated content will be stripped out later
during generation. For other properties now and in the future, that
may not be the case.
This establishes that linking is used to propagate usage-requirements
between targets in CMake code. The use of the target_link_libraries
command as the API for this is chosen because introducing a new command
would introduce confusion due to multiple commands which differ only in
a subtle way.
This is both a short form of using a TARGET_DEFINED expression
together with a TARGET_PROPERTY definition, and a way to strip
non-target content from interface properties when exporting.
Projects set interface requirements upstream, and existing
downstreams use of target_link_libraries will consume those interfaces.
This can create a backward compatibility concern as the result may
be changing the order of include directories of downstreams, or another
side-effect of using the INTERFACE properties.
Provide a way for them to emulate the behavior of a version-based
policy in the config file.
Both commit 8a37ebec (Add the target_include_directories command,
2013-01-01) and commit fc61a7a7 (Add the target_compile_definitions
command, 2013-01-08) added command implementations deriving from the new
cmTargetPropCommandBase class. Fix cmTypeMacro declarations of the
inheritance relationship.
7bf490e Make subclasses responsible for joining content.
f6b16d4 Don't allow targets args in the new target commands.
b3a7e19 Make the Property name protected so that subclasses can use it.
We need to make sure we can export targets which have content such
as $<0:$<TARGET_PROPERTY:not_a_target,INTERFACE_INCLUDE_DIRECTORIES>
That means making not finding a target non-fatal here.
Explain in the documentation for the legacy signature
target_link_libraries(foo bar)
that the other signatures like
target_link_libraries(foo LINK_INTERFACE_LIBRARIES ...)
target_link_libraries(foo LINK_PRIVATE ...)
will set the LINK_INTERFACE_LIBRARIES target property and therefore make
libraries specified only by the legacy signature private.
These interface-related link-libraries properties are used to determine
the value of the other INTERFACE properties, so we were getting infinite
recursion and segfaults otherwise.
6063fef Output include directories as LOG messages, not warnings.
aa66748 Specify the target whose includes are being listed.
d70204a Only output includes once after the start of 'generate-time' when debugging.
0d46e9a Store includes from the same include_directories call together.
830246e Export the COMPATIBLE_INTERFACE_BOOL content properties
bd82bb4 Clear the link information in ClearLinkMaps.
e987991 Make INTERFACE determined properties readable in generator expressions.
d9afacc Exit early if we find an inconsistent property.
1800f70 Populate the link information cache before checking dependent properties.
With similar reasoning to the parent commit, as downstreams, we can't
determine what $<CONFIG> generator expressions would be appropriate.
Upstream would have populated the INTERFACE_INCLUDE_DIRECTORIES with
config-specific generator expressions, possibly appropriate for
their DEBUG_CONFIGURATIONS. In theory, if we would add include
directories for a DEBUG intent, we would have to match the upstream
configurations for that.
Rather than attempting to discover the appropriate configurations
at this time, simplify the feature instead. The use of IMPORTED targets
with these commands could still be added in the future if targets
would export their DEBUG_CONFIGURATIONS somehow.
This reverts commit 9cfe4f1b76.
It turns out that correctly adding the content to
the IMPORTED_LINK_INTERFACE_LIBARIES_<CONFIG> of an upstream target
from the buildsystem of a downstream project is not simple.
If upstream had added the INTERFACE content, the config-specific
properties would be determined by the DEBUG_CONFIGURATIONS of
upstream.
As downstream, we don't have any information about what
the DEBUG_CONFIGURATIONS of upstream were, so we can't determine
which configuration-specific properties to populate. The best we can do
is add it to all of them or add it to the ones downstream considers to
be DEBUG_CONFIGURATIONS, neither of which is a good solution.
So, removing the porcelain API for that is the best approach. A human
can still determine which properties to populate and use
the set_property API to populate the desired properies.
Another solution to this would be for upstream targets to publish
what they consider DEBUG_CONFIGURATIONS, but that can be added in
a future release.
During configure-time, GetIncludeDirectories may be called too, for example
if using the export() command. As the content can be different, it should
be output each time then.
Otherwise, we get a separate IncludeDirectoriesEntry for each include,
and that causes unnecessary and confusing splitting in the output when
debugging the INCLUDE_DIRECTORIES property.
The cache here needs to be cleared if GetLinkInformation is called
at configure-time, such as during an export().
The next commit does exactly that, and without this patch,
the LinkLanguage test would fail.
It is not necessary and the current state is unintentional. Before
this patch,
target_link_libraries(foo bar)
causes the LINK_LIBRARIES property of foo to contain
$<TARGET_NAME:bar>
instead of just
bar
Stephen Kelly
Brad King
Kitware Robot
Patrick Gansterer
Alex Neundorf
Rolf Eike Beer
Yury G. Kudryashov