CMake 3.12.0-rc1 is ready for testing

I am proud to announce the first CMake 3.12 release candidate.
https://cmake.org/download/

Documentation is available at:
https://cmake.org/cmake/help/v3.12

Release notes appear below and are also published at
https://cmake.org/cmake/help/v3.12/release/3.12.html

Some of the more significant changes in CMake 3.12 are:

• The “target_link_libraries()” command now supports Object
  Libraries. Linking to an object library uses its object files in
  direct dependents and also propagates usage requirements.
• The “target_link_libraries()” command may now be called to modify
  targets created outside the current directory.
• The “file(GLOB)” and “file(GLOB_RECURSE)” commands learned a new
  flag “CONFIGURE_DEPENDS” which enables expression of build system
  dependency on globbed directory’s contents.
• The “Compile Features” functionality is now aware of C++ 20. No
  specific features are yet enumerated besides the “cxx_std_20” meta-
  feature.
• The Visual Studio Generators for VS 2017 learned to support a
  “version=14.##” option in the “CMAKE_GENERATOR_TOOLSET” value (e.g.
  via the “cmake(1)” “-T” option) to specify a toolset version number.
• The “cmake(1)” Build Tool Mode (“cmake –build”) gained “–
  parallel [<jobs>]” and “-j [<jobs>]” options to specify a parallel
  build level. They map to corresponding options of the native build
  tool.
• The “add_compile_definitions()” command was added to set
  preprocessor definitions at directory level. This supersedes
  “add_definitions()”.
• The “cmake_minimum_required()” and “cmake_policy(VERSION)”
  commands now accept a version range using the form
  “<min>[…<max>]”. The “<min>” version is required but policies are
  set based on the “<max>” version. This allows projects to specify a
  range of versions for which they have been updated and avoid
  explicit policy settings.
• The “find_package()” command now searches a prefix specified by a
  “PackageName_ROOT” CMake or environment variable. Package roots are
  maintained as a stack so nested calls to all “find_*” commands
  inside find modules also search the roots as prefixes. See policy
  “CMP0074”.
• A new “$<GENEX_EVAL:…>” and “$<TARGET_GENEX_EVAL:target,…>”
  “generator expression” has been added to enable consumption of
  generator expressions whose evaluation results itself in generator
  expressions.
• A new “$<TARGET_EXISTS:…>” “generator expression” has been
  added.
• A new “$<TARGET_NAME_IF_EXISTS:…>” “generator expression” has
  been added.
• The “FindCURL” module now provides imported targets.
• The “FindJPEG” module now provides imported targets.
• A “FindODBC” module was added to find an Open Database
  Connectivity (ODBC) library.
• New “FindPython3” and “FindPython2” modules, as well as a new
  “FindPython” module, have been added to provide a new way to locate
  python environments.

CMake 3.12 Release Notes
************************

Changes made since CMake 3.11 include the following.


New Features
============


Generators
----------

* The Visual Studio Generators for VS 2017 learned to support a
  "version=14.##" option in the "CMAKE_GENERATOR_TOOLSET" value (e.g.
  via the "cmake(1)" "-T" option) to specify a toolset version number.


Command-Line
------------

* The "cmake(1)" Build Tool Mode ("cmake --build") gained "--
  parallel [<jobs>]" and "-j [<jobs>]" options to specify a parallel
  build level.  They map to corresponding options of the native build
  tool.


Commands
--------

* The "add_compile_definitions()" command was added to set
  preprocessor definitions at directory level.  This supersedes
  "add_definitions()".

* The "cmake_minimum_required()" and "cmake_policy(VERSION)"
  commands now accept a version range using the form
  "<min>[...<max>]". The "<min>" version is required but policies are
  set based on the "<max>" version.  This allows projects to specify a
  range of versions for which they have been updated and avoid
  explicit policy settings.

* The "file(GLOB)" and "file(GLOB_RECURSE)" commands learned a new
  flag "CONFIGURE_DEPENDS" which enables expression of build system
  dependency on globbed directory's contents.

* The "file(TOUCH)" and "file(TOUCH_NOCREATE)" commands were added
  to expose "TOUCH" functionality without having to use CMake's
  command- line tool mode with "execute_process()".

* The "find_package()" command now searches a prefix specified by a
  "PackageName_ROOT" CMake or environment variable.  Package roots are
  maintained as a stack so nested calls to all "find_*" commands
  inside find modules also search the roots as prefixes. See policy
  "CMP0074".

* The "install()" command learned an optional "NAMELINK_COMPONENT"
  parameter, which allows you to change the component for a shared
  library's namelink. If none is specified, the value of "COMPONENT"
  is used by default.

* The "list()" command learned a "JOIN" sub-command to concatenate
  list's elements separated by a glue string.

* The "list()" command learned a "SUBLIST" sub-command to get a
  sublist of the list.

* The "list()" command learned a "TRANSFORM" sub-command to apply
  various string transformation to list's elements.

* The "project()" command learned an optional "HOMEPAGE_URL"
  parameter which has the effect of setting variables like
  "PROJECT_HOMEPAGE_URL", "<PROJECT-NAME>_HOMEPAGE_URL" and
  "CMAKE_PROJECT_HOMEPAGE_URL".

* The "string()" command learned a "JOIN" sub-command to concatenate
  input strings separated by a glue string.

* "target_compile_options()" and "add_compile_options()" commands
  gained a "SHELL:" prefix to specify a group of related options using
  shell-like quoting.

* The "target_link_libraries()" command now supports Object
  Libraries. Linking to an object library uses its object files in
  direct dependents and also propagates usage requirements.

* The "target_link_libraries()" command may now be called to modify
  targets created outside the current directory.


Variables
---------

* The "CMAKE_FOLDER" variable was added to initialize the "FOLDER"
  property on all targets.

* The "CMAKE_DOTNET_TARGET_FRAMEWORK_VERSION" variable was defined
  to initialize all "DOTNET_TARGET_FRAMEWORK_VERSION" target
  properties.

* "CMAKE_PROJECT_VERSION*" variables have been introduced:

  * "CMAKE_PROJECT_VERSION"

  * "CMAKE_PROJECT_VERSION_MAJOR"

  * "CMAKE_PROJECT_VERSION_MINOR"

  * "CMAKE_PROJECT_VERSION_PATCH"

  * "CMAKE_PROJECT_VERSION_TWEAK"

* The "CMAKE_SUPPRESS_REGENERATION" variable was extended to support
  the "Ninja" and Makefile Generators. It is also now documented.

* "CMAKE_VS_SDK_*_DIRECTORIES" variables were defined to tell Visual
  Studio Generators for VS 2010 and above how to populate fields in
  ".vcxproj" files that specify SDK directories.  The variables are:

  * "CMAKE_VS_SDK_EXCLUDE_DIRECTORIES"

  * "CMAKE_VS_SDK_EXECUTABLE_DIRECTORIES"

  * "CMAKE_VS_SDK_INCLUDE_DIRECTORIES"

  * "CMAKE_VS_SDK_LIBRARY_DIRECTORIES"

  * "CMAKE_VS_SDK_LIBRARY_WINRT_DIRECTORIES"

  * "CMAKE_VS_SDK_REFERENCE_DIRECTORIES"

  * "CMAKE_VS_SDK_SOURCE_DIRECTORIES"

* A "MSVC_TOOLSET_VERSION" variable was added to provide the MSVC
  toolset version associated with the current MSVC compiler version in
  "MSVC_VERSION".


Properties
----------

* The "COMMON_LANGUAGE_RUNTIME" target property was introduced to
  configure the use of managed C++ for Visual Studio Generators for VS
  2010 and above. A corresponding "IMPORTED_COMMON_LANGUAGE_RUNTIME"
  target property was added to support "C++/CLI" for imported targets.

* The "DOTNET_TARGET_FRAMEWORK_VERSION" target property was
  introduced as replacement for "VS_DOTNET_TARGET_FRAMEWORK_VERSION",
  which is considered deprecated now.

* An "EXPORT_PROPERTIES" target property was added to specify a
  custom list of target properties to include in targets exported by
  the "install(EXPORT)" and "export()" commands.

* The "PDB_OUTPUT_DIRECTORY" property learned to support "generator
  expressions".

* A "TESTS" directory property was added to hold the list of tests
  defined by the "add_test()" command.

* A "VS_DEBUGGER_COMMAND" target property was created to set the
  debugging command line with Visual Studio Generators for VS 2010 and
  above.

* HLSL source file properties "VS_SHADER_DISABLE_OPTIMIZATIONS" and
  "VS_SHADER_ENABLE_DEBUG" gained support for generator expressions.

* HLSL source file property "VS_SHADER_OBJECT_FILE_NAME" has been
  added to the Visual Studio Generators for VS 2010 and above. The
  property specifies the file name of the compiled shader object.


Modules
-------

* The "FindALSA" module now provides imported targets.

* The "FindCURL" module now provides imported targets.

* The "FindJPEG" module now provides imported targets.

* The "FindLibXml2" module now provides imported targets.

* A "FindODBC" module was added to find an Open Database
  Connectivity (ODBC) library.

* The "FindPkgConfig" module has learned to export the found
  libraries with full path for direct consumption with the
  "target_link_libraries()" command.

* New "FindPython3" and "FindPython2" modules, as well as a new
  "FindPython" module, have been added to provide a new way to locate
  python environments.

* The "UseSWIG" module gained a whole refresh and is now more
  consistent with standard CMake commands to generate libraries and is
  fully configurable through properties.

* The "UseSWIG" module learned to manage multiple behaviors through
  "UseSWIG_MODULE_VERSION" variable to ensure legacy support as well
  as more robust handling of "SWIG" advanced features (like
  "%template").

* The "UseSWIG" module learned to support CSHARP variant wrapper
  files.

* The "WriteCompilerDetectionHeader" module gained a "BARE_FEATURES"
  option to add a compatibility define for the exact keyword of a new
  language feature.


Generator Expressions
---------------------

* A new "$<GENEX_EVAL:...>" and "$<TARGET_GENEX_EVAL:target,...>"
  "generator expression" has been added to enable consumption of
  generator expressions whose evaluation results itself in generator
  expressions.

* A new "$<IN_LIST:...>" "generator expression" has been added.

* A new "$<TARGET_EXISTS:...>" "generator expression" has been
  added.

* A new "$<TARGET_NAME_IF_EXISTS:...>" "generator expression" has
  been added.


CTest
-----

* The "ctest_start()" command has been reworked so that you can
  simply call "ctest_start(APPEND)" and it will read all the needed
  information from the TAG file. The argument parsing has also been
  relaxed so that the order of the arguments is less significant.

* A "PROCESSOR_AFFINITY" test property was added to request that
  CTest run a test with CPU affinity for a set of processors disjoint
  from other concurrently running tests with the property set.


CPack
-----

* The "CPack" module now uses variables
  "CMAKE_PROJECT_VERSION_MAJOR", "CMAKE_PROJECT_VERSION_MINOR" and
  "CMAKE_PROJECT_VERSION_PATCH" to initialize corresponding CPack
  variables.

* "cpack(1)" gained basic support for NuGet. See the "CPackNuGet"
  module.


Other
-----

* The "Compile Features" functionality is now aware of C++ 20.  No
  specific features are yet enumerated besides the "cxx_std_20" meta-
  feature.

* The "Compile Features" functionality is now aware of the
  availability of C features in MSVC since VS 2010.

* The "Compile Features" functionality is now aware of C language
  standards supported by Texas Instruments C compilers.


Deprecated and Removed Features
===============================

* The "Visual Studio 8 2005" generator has been removed.

* CMake no longer produces "<tgt>_LIB_DEPENDS" cache entries for
  library targets.  See policy "CMP0073".


Other Changes
=============

* Include flags for directories marked as "SYSTEM" are now moved
  after non-system directories.  The "-isystem" flag does this
  automatically, so moving them explicitly to the end makes the
  behavior consistent on compilers that do not have any "-isystem"
  flag.

* Fortran dependency scanning now supports dependencies implied by
  Fortran Submodules.

* The existence and functionality of the file
  "${CMAKE_BINARY_DIR}/cmake_install.cmake" has now been documented in
  the "install()" documentation so that external packaging software
  can take advantage of CPack-style component installs.

* The "CheckIncludeFile" module "check_include_file" macro learned
  to honor the "CMAKE_REQUIRED_LIBRARIES" variable. See policy
  "CMP0075".

* The "CheckIncludeFileCXX" module "check_include_file_cxx" macro
  learned to honor the "CMAKE_REQUIRED_LIBRARIES" variable. See policy
  "CMP0075".

* The "CheckIncludeFiles" module "check_include_files" macro learned
  to honor the "CMAKE_REQUIRED_LIBRARIES" variable. See policy
  "CMP0075".

* The "cmake(1)" "-E copy_directory" tool now fails when the source
  directory does not exist.  Previously it succeeded by creating an
  empty destination directory.

* The "UseSWIG" module "swig_add_library()" command (and legacy
  "swig_add_module" command) now set the prefix of Java modules to
  """" for MINGW, MSYS, and CYGWIN environments.