77d2646784
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.
This is CMake, the cross-platform, open-source make system. CMake is distributed under the BSD License, see Copyright.txt. For documentation see the Docs/ directory once you have built CMake or visit http://www.cmake.org. Building CMake ============== Supported Platforms ------------------- MS Windows, Mac OS X, Linux, FreeBSD, Solaris, HP-UX, IRIX, BeOS, QNX Other UNIX-like operating systems may work too out of the box, if not it shouldn't be a major problem to port CMake to this platform. Contact the CMake mailing list in this case: http://www.cmake.org/mailman/listinfo/cmake If you don't have any previous version of CMake already installed -------------------------------------------------------------- * UNIX/Mac OSX/MinGW/MSYS/Cygwin: You need to have a compiler and a make installed. Run the bootstrap script you find the in the source directory of CMake. You can use the --help option to see the supported options. You may want to use the --prefix=<install_prefix> option to specify a custom installation directory for CMake. You can run the bootstrap script from within the CMake source directory or any other build directory of your choice. Once this has finished successfully, run make and make install. So basically it's the same as you may be used to from autotools-based projects: $ ./bootstrap; make; make install * Other Windows: You need to download and install a binary release of CMake in order to build CMake. You can get these releases from http://www.cmake.org/HTML/Download.html . Then proceed with the instructions below. You already have a version of CMake installed --------------------------------------------- You can build CMake as any other project with a CMake-based build system: run the installed CMake on the sources of this CMake with your preferred options and generators. Then build it and install it. For instructions how to do this, see http://www.cmake.org/HTML/RunningCMake.html