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
This new expression allows checking how a policy was set when a target
was created. That information is only recorded for a subset of policies,
so a whitelist is used.
1d74ba2 Test evaluation target via export for generator expressions
522bdac Export the INTERFACE_PIC property.
4ee872c Make the BUILD_INTERFACE of export()ed targets work.
1d47cd9 Add a test for the interfaces in targets exported from the build tree.
6c828f9 Move the exported check for file existence.
cfd4f0a Move the exported check for dependencies of targets
d8fe1fc Only generate one check per missing target.
f623d37 Don't write a comment in the export file without the code.
b279f2b Strip consecutive semicolons when preprocessing genex strings.
Don't add generator expressions to variables which are used
for CMP0003, CMP0004, and the old-style _LIB_DEPENDS content. They
will not be evaluated when read anyway and would probably confuse
the code reading them.
This makes it legitimate to use target_link_libraries with generator
expressions as arguments.
77d2646 Allow generator expressions in LINK_INTERFACE_LIBRARIES.
94aeaf7 Split LINK_INTERFACE_LIBRARIES export handling into dedicated method.
a3aedb8 Split the generator expression before extracting targets.
b6036d1 Extract the AddTargetNamespace method.
cb1afbf Don't pass a position when determining if a target name is a literal.
f99196d Add cmGeneratorExpression::Split() API.
In the implementation of "cmake -E cmake_link_script", skip lines from
the input file that are empty or contain only whitespace. Do not try to
run a child with no command line.
The Config and IMPORTED_ variants may also contain generator
expressions.
If 'the implementation is the interface', then the result of
evaluating the expressions at generate time is used to populate
the IMPORTED_LINK_INTERFACE_LIBRARIES property.
1) In the case of non-static libraries, this is fine because the
user still has the option to populate the LINK_INTERFACE_LIBRARIES
with generator expressions if that is what is wanted.
2) In the case of static libraries, this prevents a footgun,
enforcing that the interface and the implementation are really
the same.
Otherwise, the LINK_LIBRARIES could contain a generator
expression which is evaluated with a different context at build
time, and when used as an imported target. That would mean that the
result of evaluating the INTERFACE_LINK_LIBRARIES property for
a static library would not necessarily be the 'link implementation'.
For example:
add_library(libone STATIC libone.cpp)
add_library(libtwo STATIC libtwo.cpp)
add_library(libthree STATIC libthree.cpp)
target_link_libraries(libtwo
$<$<STREQUAL:$<TARGET_PROPERTY:TYPE>,STATIC_LIBRARY>:libone>)
target_link_libraries(libthree libtwo)
If the LINK_LIBRARIES content was simply copied to the
IMPORTED_LINK_INTERFACE_LIBRARIES, then libthree links to libone, but
executables linking to libthree will not link to libone.
3) As the 'implementation is the interface' concept is to be
deprecated in the future anyway, this should be fine.
Now that we're processing a LINK_INTERFACE_LIBRARIES string, it
can contain targets. Make sure they are extracted for
namespacing purposes.
This needs to be restricted to strings which can actually have
targets named in them. For example, this is not done for
INTERFACE_COMPILE_DEFINITIONS, because even if there is a target
named 'foo', the string 'foo' in that property means that '-Dfoo'
will be set when compiling.
3581b96 Process the INTERFACE_PIC property from linked dependencies
042ecf0 Add API to calculate link-interface-dependent bool properties or error.
bf5ece5 Keep track of properties used to determine linker libraries.
0380f36 FindOpenGL: add Haiku paths
8e9630c FindGLUT: BeOS does not have libXi and libXmu
50bfedf FindLua51: do not try to link libm on BeOS
3d2e6a0 check for Haiku only with __HAIKU__
7a1b961 Haiku no longer defines __BEOS__
ed96d9a bootstrap: use better defaults for Haiku
This allows a dependee to inform a target that it should have its
POSITION_INDEPENDENT_CODE property set to ON, or OFF. The value of
the POSITION_INDEPENDENT_CODE property, if set, must be consistent
with any INTERFACE_POSITION_INDEPENDENT_CODE properties on dependees.
Add a test covering the consistency checks on platforms where they run.
This new method checks that the property FOO on a target is consistent
with the INTERFACE_FOO properties of its dependees. If they are not the
consistent, an error is reported. 'Consistent' means that iff the
property is set, it must have the same boolean value as all other
related properties.
This makes
set(CMAKE_BUILD_INTERFACE_INCLUDES ON)
add the equivalent of
set_property(TARGET tgt APPEND PROPERTY
INTERFACE_INCLUDE_DIRECTORIES
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR};${CMAKE_CURRENT_BINARY_DIR}>
)
to every target.
If the headers are in CMAKE_CURRENT_SOURCE_DIR, and the generated headers
are in CMAKE_CURRENT_BINARY_DIR, this is a convenient way to build a target
bar, which depends on foo, just by using target_link_libraries() and adding
the INTERFACE_INCLUDE_DIRECTORIES to the INCLUDE_DIRECTORIES of the target
being linked. There will be more-convenient porcelain API to consume the
property in the future.
This makes it possible to use:
target_link_libraries(foo LINK_INTERFACE_LIBRARIES bar)
where foo is an IMPORTED target. Other tll() signatures are not
allowed.
Previously we kept direct link dependencies in OriginalLinkLibraries.
The property exposes the information in the CMake language through the
get/set_property commands. We preserve the OriginalLinkLibraries value
internally to support old APIs like that for CMP0003's OLD behavior, but
the property is now authoritative. This follows up from commit d5cf644a
(Split link information processing into two steps, 2012-11-01).
This will be used later to populate the link interface properties when
exporting targets, and will later allow use of generator expressions
when linking to libraries with target_link_libraries.
Also make targets depend on the (config-specific) union of dependencies.
CMake now allows linking to dependencies or not depending on the config.
However, generated build systems are not all capable of processing
config-specific dependencies, so the targets depend on the union of
dependencies for all configs.
The 'head' is the dependent target to be linked with the current target.
It will be used to evaluate generator expressions with proper handling
of mapped configurations and is used as the source target of properties.
This requires that memoization is done with a key of a pair of target
and config, instead of just config, because now the result also depends
on the target. Removing the memoization entirely is not an option
because it slows cmake down considerably.
cc676c3 OS X: Detect implicit linker framework search paths
2dd67c7 OS X: Detect implicit link directories on modern toolchains
ba58d0c OS X: Link with all framework search paths, not just the last
894f52f Handle INTERFACE properties transitively for includes and defines.
f5b1980 Populate the ExportedTargets member early in GenerateMainFile
c67b812 Make cycles in target properties ignored, not an error.
d0f950f Use mapped config properties to evaluate $<CONFIG>
26def17 Make all relevant targets available in the genex context.
0c657dc Add API to populate INTERFACE properties in exported targets.
e04f737 Add API to extract target names from a genex string.
b0c8f73 Add the TARGET_NAME generator expression.
77475fe Allow generator expressions to require literals.
b2f1700 GenEx: Add expressions to specify build- or install-only values
Since commit 9a6ff950 (Fix for bug where VS2010 did not use .obj files as
part of the build, 2011-04-01) and commit b291d9e7 (VS10: Fix external
objects generated outside target, 2012-03-19) we try to detect whether an
external object file is also a custom command output in the same target.
This is because VS10 includes .obj custom command outputs on the link line
by default.
VS 11 supports a "<LinkObjects ...>false</LinkObjects>" setting in custom
command rules to tell VS not to link the outputs. From the VS help:
Specify whether the Inputs and output files with specific extensions (.obj,
.lib, .res, .rsc) are passed to the linker.
Treat all external object files the same and add "<Object>" settings for them.
The member variable is checked to determine whether to call
HandleMissingTarget(). As that could be called during the loop in
the comming commits, ensure that it contains all targets being
exported.
Constructs such as these are an error as they are direct self-references:
set_property(TARGET foo APPEND PROPERTY
INCLUDE_DIRECTORIES $<TARGET_PROPERTY:foo,INCLUDE_DIRECTORIES>)
set_property(TARGET foo APPEND PROPERTY
INCLUDE_DIRECTORIES $<TARGET_PROPERTY:INCLUDE_DIRECTORIES>)
However, this is an indirect self-reference in a cycle, and not an error:
set_property(TARGET foo APPEND PROPERTY
INCLUDE_DIRECTORIES $<TARGET_PROPERTY:bar,INCLUDE_DIRECTORIES>)
set_property(TARGET bar APPEND PROPERTY
INCLUDE_DIRECTORIES $<TARGET_PROPERTY:foo,INCLUDE_DIRECTORIES>)
The TARGET_NAME expression, which requires a literal, provides
target names. $<TARGET_PROPERTY:tgt,prop> also provides target
names in the cases where tgt is a literal, so that TARGET_NAME is
not needed then in addition.
This is for specifying INCLUDE_DIRECTORIES relevant to the build-location
or the install location for example:
set_property(TARGET foo PROPERTY
INTERFACE_INCLUDE_DIRECTORIES
"$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR};${CMAKE_CURRENT_SOURCE_DIR}>"
"$<INSTALL_INTERFACE:${CMAKE_INSTALL_PREFIX}/include>"
)
A 'bar' target can then use:
set_property(TARGET bar PROPERTY
INCLUDE_DIRECTORIES
"$<TARGET_PROPERTY:foo,INTERFACE_INCLUDE_DIRECTORIES>"
)
and it will work whether foo is in the same project, or an imported target
from an installation location, or an imported target from a build location
generated by the export() command.
Because the generator expressions are only evaluated at build-time, these
new expressions are equivalent to the ZeroNode and OneNode.
The GeneratorExpression test is split into parts. Some shells can't run
the custom command as it is getting too long.
Xcode and VS <= 7.1 will not build targets that have no source files
besides $<TARGET_OBJECTS:...>. Suggest in the documentation that
projects always add at least one real source file.
0941d62 Add a way to print the origins of used include directories.
18a3195 Keep track of INCLUDE_DIRECTORIES as a vector of structs.
76ea420 Use cmsys::auto_ptr to manage cmCompiledGeneratorExpressions
Note it is still possible for CTest to start more than the number of
processes specified by PARALLEL_LEVEL, but this prevents the number of
tests to start from being unbounded because of overflow.
Previously we hard-coded a list of implicit framework directories but
did not account for CMAKE_OSX_SYSROOT or for changes to the list across
OS X versions. Instead we should automatically detect the framework
directories for the active toolchain.
The parent commit added the "-Wl,-v" option to ask "ld" to print its
implicit directories. It displays a block such as:
Framework search paths:
/...
Parse this block to extract the list of framework directories.
Detection may fail on toolchains that do not list their framework
directories, such as older OS X linkers. Always treat the paths
<sdk>/Library/Frameworks
<sdk>/System/Library/Frameworks
<sdk>/Network/Library/Frameworks # Older OS X only
/System/Library/Frameworks
as implicit. Note that /System/Library/Frameworks should always be
considered implicit so that frameworks CMake finds there will not
override the SDK copies.
Refactoring in commit 8d674e78 (Ninja: move -LIBPATH behind -link
option, 2012-09-26) accidentally added code that overwrites the
framework search path flags on each iteration instead of appending.
Change '=' to '+=' to fix it. This affects Makefile and Ninja
generators.
Extend documentation for CMAKE_<LANG>_IMPLICIT_LINK_DIRECTORIES to
explain how it is used by CMake and how it can be influenced by
environment variables.
Inspired-by: Alex Neundorf <neundorf@kde.org>
f0d9385 Makefile: Use modern link information for framework search paths
2bc22bd Xcode: Add frameworks search paths from link dependeny closure (#13397)
Use cmComputeLinkInformation::GetFrameworkPaths to get the list of
framework paths needed by the linker. Drop the now unused framework
information from the old-style cmTarget link dependency analysis.
This should finally fix#13667 and #13762.
Instead of adding special handling to guess whether implicit include dirs
may have been removed, simply make it possible to query the include dirs
without removing the implicit ones.
Alex
The Xcode generator produces FRAMEWORK_SEARCH_PATHS from:
(1) Include directories of the form /path/to/Foo.framework become
-F/path/to so '#include <Foo/H>' can find H in the framework.
(2) Linked frameworks of the form /path/to/Foo.framework become
-F/path/to -framework Foo so the linker can find the framework.
Originally commit 82bb6fae (add framework support to FIND_FILE,
2005-12-27) added these and used the (then current) old-style link
dependency analysis results to get the frameworks. Later a second
setting was added by commit 2ed6191f (add initial xcode framework stuff,
2007-05-08) to transform -F/path/to linker options produced by the old
link line generation into entries appended to FRAMEWORK_SEARCH_PATHS.
Then commit 96fd5909 (Implement linking with paths to library files,
2008-01-22) updated the second setting to directly use the results of
full modern link dependency analysis, but forgot to remove the use of
old-style link results from the original setting location.
The two settings worked together for a while, with the second one
appending to the first. Then commit f33a27ab (Generate native Xcode 3.0
and 3.1 projects, 2009-06-29) changed the internal representation format
produced by the first setting but did not update the second setting to
append to the new representation. As a result, if the first setting
added any paths (usually via the old-style link analysis) then the
second setting containing the modern link analysis results would not be
applied at all.
Fix this by removing use of the old-style link analysis results.
Replace it using the modern link dependencies and remove the second
setting altogether. Now all values for FRAMEWORK_SEARCH_PATHS are
collected in one place so no special append logic is needed.
Stephen Kelly
Kitware Robot
Robert Maynard
Brad King
Yury G. Kudryashov
Rolf Eike Beer
Peter Kümmel
Eric LaFranchi
David Cole
Casey Goodlett
Alex Neundorf