CMake 3.1-rc1 is now ready!

I am proud to announce that CMake 3.1 has entered the release candidate stage.

Sources and binaries are available at:
  http://www.cmake.org/files/v3.1/?C=M;O=D

Documentation is available at:
  http://www.cmake.org/cmake/help/v3.1

Release notes appear below and are also published at
  http://www.cmake.org/cmake/help/v3.1/release/3.1.0.html

Some of the more significant features of CMake 3.1 are:

* Windows Phone and Windows Store support has been added to  Visual Studio 11
  (2012) and above Generators.

* NVIDIA Nsight Tegra support has been added to  Visual Studio 10 (2010) and
  above Generators.

* New "target_compile_features" command allows populating target based compile
  features. CMake uses this information to ensure that the compiler in use is
  capable of building the target, and to add any necessary compile flags
  such as -std=gnu++11 to support language features.
  More information on this is found at:
  – http://www.cmake.org/cmake/help/v3.1/manual/cmake-compile-features.7.html

* The syntax for *Variable References* and *Escape Sequences* was simplified in
  order to allow a much faster implementation. See policy "CMP0053".

* The "if" command no longer automatically dereferences variables named in
  quoted or bracket arguments.  See policy "CMP0054".

* The target property "SOURCES" now generally supports "Generator Expressions".
  The generator expressions may be used in the "add_library" and
  "add_executable" commands.

* It is now possible to write and append to the target property "SOURCES".
  The variable "CMAKE_DEBUG_TARGET_PROPERTIES" can be used to trace the
  origin of sources.

* CPack gained "7Z" and "TXZ" generators supporting lzma-compressed archives.

* The ExternalProject module has learned to support lzma-compressed
  source tarballs with ".7z", ".tar.xz", and ".txz" extensions.

* The ExternalProject module ExternalProject_Add command learned a new
  BUILD_ALWAYS option to cause the external project build step to run every
  time the host project is built.

* The ctest_coverage command learned to support Intel coverage files with the
  "codecov" tool.

* The ctest_memcheck command learned to support sanitizer modes, including
  "AddressSanitizer", "MemorySanitizer", "ThreadSanitizer", and
  "UndefinedBehaviorSanitizer".

Deprecated and Removed Features:

* In CMake 3.0 the "target_link_libraries" command accidentally began allowing
  unquoted arguments to use Generator Expressions containing a semicolon
  separated list within them. For example:

    set(libs B C)
    target_link_libraries(A PUBLIC $<BUILD_INTERFACE:${libs}>)

  This is equivalent to writing:

    target_link_libraries(A PUBLIC $<BUILD_INTERFACE:B C>)

  and was never intended to work. It did not work in CMake 2.8.12.
  Such generator expressions should be in quoted arguments:

    set(libs B C)
    target_link_libraries(A PUBLIC "$<BUILD_INTERFACE:${libs}>")

  CMake 3.1 again requires the quotes for this to work correctly.

CMake 3.1.0 Release Notes
*************************

Changes made since CMake 3.0.0 include the following.

Documentation Changes
=====================

* A new "cmake-compile-features(7)" manual was added.

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

Generators
———-

* A "Visual Studio 14" generator was added.

Windows Phone and Windows Store
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* Generators for Visual Studio 11 (2012) and above learned to
  generate projects for Windows Phone and Windows Store.  One may set
  the "CMAKE_SYSTEM_NAME" variable to "WindowsPhone" or "WindowsStore"
  on the "cmake(1)" command-line or in a "CMAKE_TOOLCHAIN_FILE" to
  activate these platforms. Also set "CMAKE_SYSTEM_VERSION" to "8.0"
  or "8.1" to specify the version of Windows to be targeted.

NVIDIA Nsight Tegra
~~~~~~~~~~~~~~~~~~~

* Generators for Visual Studio 10 (2010) and above learned to
  generate projects for NVIDIA Nsight Tegra Visual Studio Edition.
  One may set the "CMAKE_SYSTEM_NAME" variable to "Android" on the
  "cmake(1)" command-line or in a "CMAKE_TOOLCHAIN_FILE" to activate
  this platform.

Syntax
——

* The "cmake-language(7)" syntax for *Variable References* and
  *Escape Sequences* was simplified in order to allow a much faster
  implementation.  See policy "CMP0053".

* The "if()" command no longer automatically dereferences variables
  named in quoted or bracket arguments.  See policy "CMP0054".

Commands
——–

* The "add_custom_command()" command learned to interpret "cmake-
  generator-expressions(7)" in arguments to "DEPENDS".

* The "export(PACKAGE)" command learned to check the
  "CMAKE_EXPORT_NO_PACKAGE_REGISTRY" variable to skip exporting the
  package.

* The "file(STRINGS)" command gained a new "ENCODING" option to
  enable extraction of "UTF-8" strings.

* The "find_package()" command learned to check the
  "CMAKE_FIND_PACKAGE_NO_PACKAGE_REGISTRY" and
  "CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY" variables to skip
  searching the package registries.

* The "install()" command learned a "MESSAGE_NEVER" option to avoid
  output during installation.

* The "string()" command learned a new "GENEX_STRIP" subcommand
  which removes "generator expression".

* The "string()" command learned a new "UUID" subcommand to generate
  a univerally unique identifier.

* New "target_compile_features()" command allows populating the
  "COMPILE_FEATURES" target property, just like any other build
  variable.

* The "target_sources()" command was added to add to the "SOURCES"
  target property.

Variables
———

* The Visual Studio generators for versions 8 (2005) and above
  learned to read the target platform name from a new
  "CMAKE_GENERATOR_PLATFORM" variable when it is not specified as part
  of the generator name.  The platform name may be specified on the
  "cmake(1)" command line with the "-A" option, e.g. "-G "Visual
  Studio 12 2013" -A x64".

* The "CMAKE_GENERATOR_TOOLSET" variable may now be initialized in a
  toolchain file specified by the "CMAKE_TOOLCHAIN_FILE" variable.
  This is useful when cross-compiling with the Xcode or Visual Studio
  generators.

* The "CMAKE_INSTALL_MESSAGE" variable was introduced to optionally
  reduce output installation.

Properties
———-

* New "CXX_STANDARD" and "CXX_EXTENSIONS" target properties may
  specify values which CMake uses to compute required compile options
  such as "-std=c++11" or "-std=gnu++11". The "CMAKE_CXX_STANDARD" and
  "CMAKE_CXX_EXTENSIONS" variables may be set to initialize the target
  properties.

* New "C_STANDARD" and "C_EXTENSIONS" target properties may specify
  values which CMake uses to compute required compile options such as
  "-std=c11" or "-std=gnu11". The "CMAKE_C_STANDARD" and
  "CMAKE_C_EXTENSIONS" variables may be set to initialize the target
  properties.

* New "COMPILE_FEATURES" target property may contain a list of
  features required to compile a target.  CMake uses this information
  to ensure that the compiler in use is capable of building the
  target, and to add any necessary compile flags to support language
  features.

* New "COMPILE_PDB_NAME" and "COMPILE_PDB_OUTPUT_DIRECTORY" target
  properties were introduced to specify the MSVC compiler program
  database file location ("cl /Fd").  This complements the existing
  "PDB_NAME" and "PDB_OUTPUT_DIRECTORY" target properties that specify
  the linker program database file location ("link /pdb").

* The "INTERFACE_LINK_LIBRARIES" target property now supports a
  "$<LINK_ONLY:…>" "generator expression".

* A new "INTERFACE_SOURCES" target property was introduced. This is
  consumed by dependent targets, which compile and link the listed
  sources.

* The "SOURCES" target property now contains "generator expression"
  such as "TARGET_OBJECTS" when read at configure time, if policy
  "CMP0051" is "NEW".

* The "SOURCES" target property now generally supports "generator
  expression".  The generator expressions may be used in the
  "add_library()" and "add_executable()" commands.

* It is now possible to write and append to the "SOURCES" target
  property.  The "CMAKE_DEBUG_TARGET_PROPERTIES" variable may be used
  to trace the origin of sources.

* A "VS_DEPLOYMENT_CONTENT" source file property was added to tell
  the Visual Studio generators to mark content for deployment in
  Windows Phone and Windows Store projects.

* The "VS_WINRT_COMPONENT" target property was created to tell
  Visual Studio generators to compile a shared library as a Windows
  Runtime (WinRT) component.

* The "Xcode" generator learned to check source file properties
  "XCODE_EXPLICIT_FILE_TYPE" and "XCODE_LAST_KNOWN_FILE_TYPE" for a
  custom Xcode file reference type.

Modules
——-

* The "BundleUtilities" module learned to resolve and replace
  "@rpath" placeholders on OS X to correctly bundle applications using
  them.

* The "CMakePackageConfigHelpers" module
  "configure_package_config_file()" command learned a new
  "INSTALL_PREFIX" option to generate package configuration files
  meant for a prefix other than "CMAKE_INSTALL_PREFIX".

* The "CheckFortranSourceCompiles" module was added to provide a
  "CHECK_Fortran_SOURCE_COMPILES" macro.

* The "ExternalData" module learned to tolerate a "DATA{}" reference
  to a missing source file with a warning instead of rejecting it with
  an error.  This helps developers write new "DATA{}" references to
  test reference outputs that have not yet been created.

* The "ExternalProject" module learned to support lzma-compressed
  source tarballs with ".7z", ".tar.xz", and ".txz" extensions.

* The "ExternalProject" module "ExternalProject_Add" command learned
  a new "BUILD_ALWAYS" option to cause the external project build step
  to run every time the host project is built.

* The "ExternalProject" module "ExternalProject_Add" command learned
  a new "EXCLUDE_FROM_ALL" option to cause the external project target
  to have the "EXCLUDE_FROM_ALL" target property set.

* The "ExternalProject" module "ExternalProject_Add_Step" command
  learned a new "EXCLUDE_FROM_MAIN" option to cause the step to not be
  a direct dependency of the main external project target.

* The "ExternalProject" module "ExternalProject_Add" command learned
  a new "DOWNLOAD_NO_PROGRESS" option to disable progress output while
  downloading the source tarball.

* The "FeatureSummary" module "feature_summary" API learned to
  accept multiple values for the "WHAT" option and combine them
  appropriately.

* The "FindCUDA" module learned to support "fatbin" and "cubin"
  modules.

* The "FindGTest" module "gtest_add_tests" macro learned a new
  "AUTO" option to automatically read the "SOURCES" target property of
  the test executable and scan the source files for tests to be added.

* The "FindGLEW" module now provides imported targets.

* The "FindGLUT" module now provides imported targets.

* The "FindHg" module gained a new "Hg_WC_INFO" macro to help run
  "hg" to extract information about a Mercurial work copy.

* The "FindOpenCL" module was introduced.

* The "FindOpenGL" module now provides imported targets "OpenGL::GL"
  and "OpenGL::GLU" when the libraries are found.

* The "FindOpenMP" module learned to support Fortran.

* The "FindPkgConfig" module learned to use the "PKG_CONFIG"
  environment variable value as the "pkg-config" executable, if set.

* The "FindVTK" module dropped support for finding VTK 4.0. It is
  now a thin-wrapper around "find_package(VTK … NO_MODULE)". This
  produces much clearer error messages when VTK is not found.

* The "FindZLIB" module now provides imported targets.

* The "GenerateExportHeader" module "generate_export_header"
  function learned to allow use with *Object Libraries*.

* The "InstallRequiredSystemLibraries" module gained a new
  "CMAKE_INSTALL_OPENMP_LIBRARIES" option to install MSVC OpenMP
  runtime libraries.

* The "UseSWIG" module learned to detect the module name from ".i"
  source files if possible to avoid the need to set the
  "SWIG_MODULE_NAME" source file property explicitly.

* The "WriteCompilerDetectionHeader" module was added to allow
  creation of a portable header file for compiler optional feature
  detection.

Generator Expressions
———————

* New "COMPILE_FEATURES" "generator expression" allows setting build
  properties based on available compiler features.

CTest
—–

* The "ctest_coverage()" command learned to read variable
  "CTEST_COVERAGE_EXTRA_FLAGS" to set "CoverageExtraFlags".

* The "ctest_coverage()" command learned to support Intel coverage
  files with the "codecov" tool.

* The "ctest_memcheck()" command learned to support sanitizer modes,
  including "AddressSanitizer", "MemorySanitizer", "ThreadSanitizer",
  and "UndefinedBehaviorSanitizer". Options may be set using the new
  "CTEST_MEMORYCHECK_SANITIZER_OPTIONS" variable.

CPack
—–

* "cpack(1)" gained an "IFW" generator to package using Qt Framework
  Installer tools.  See the "CPackIFW" module.

* "cpack(1)" gained "7Z" and "TXZ" generators supporting lzma-
  compressed archives.

* The "CPackDeb" module learned a new
  "CPACK_DEBIAN_COMPRESSION_TYPE" variable to set the tarball
  compression type.

* The "cpack(1)" "WiX" generator learned to support a
  "CPACK_WIX_ACL" installed file property to specify an Access Control
  List.

Other
—–

* The "cmake(1)" "-E" option learned a new "env" command.

* The "cmake(1)" "-E tar" command learned to support lzma-compressed
  files.

* *Object Libraries* may now have extra sources that do not compile
  to object files so long as they would not affect linking of a normal
  library (e.g. ".dat" is okay but not ".def").

* Visual Studio generators for VS 8 and later learned to support the
  "ASM_MASM" language.

* The Visual Studio generators learned to treat ".hlsl" source files
  as High Level Shading Language sources (using "FXCompile" in
  ".vcxproj" files).  A "VS_SHADER_TYPE" source file property was
  added to specify the Shader Type.

New Diagnostics
===============

* Policy "CMP0052" introduced to control directories in the
  "INTERFACE_INCLUDE_DIRECTORIES" of exported targets.

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

* In CMake 3.0 the "target_link_libraries()" command accidentally
  began allowing unquoted arguments to use "generator expressions"
  containing a (";" separated) list within them.  For example:

     set(libs B C)
     target_link_libraries(A PUBLIC $<BUILD_INTERFACE:${libs}>)

  This is equivalent to writing:

     target_link_libraries(A PUBLIC $<BUILD_INTERFACE:B C>)

  and was never intended to work.  It did not work in CMake 2.8.12.
  Such generator expressions should be in quoted arguments:

     set(libs B C)
     target_link_libraries(A PUBLIC "$<BUILD_INTERFACE:${libs}>")

  CMake 3.1 again requires the quotes for this to work correctly.

* Callbacks established by the "variable_watch()" command will no
  longer receive the "ALLOWED_UNKNOWN_READ_ACCESS" access type when
  the undocumented "CMAKE_ALLOW_UNKNOWN_VARIABLE_READ_ACCESS" variable
  is set.  Uninitialized variable accesses will always be reported as
  "UNKNOWN_READ_ACCESS".

* The "CMakeDetermineVSServicePack" module now warns that it is
  deprecated and should not longer be used.  Use the
  "CMAKE_<LANG>_COMPILER_VERSION" variable instead.

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

* The "cmake-gui(1)" learned to capture output from child processes
  started by the "execute_process()" command and display it in the
  output window.

* The "cmake-language(7)" internal implementation of generator
  expression and list expansion parsers have been optimized and shows
  non-trivial speedup on large projects.

* The Makefile generators learned to use response files with GNU
  tools on Windows to pass library directories and names to the
  linker.

* When generating linker command-lines, CMake now avoids repeating
  items corresponding to SHARED library targets.

* Support for the Open Watcom compiler has been overhauled. The
  "CMAKE_<LANG>_COMPILER_ID" is now "OpenWatcom", and the
  "CMAKE_<LANG>_COMPILER_VERSION" now uses the Open Watcom external
  version numbering.  The external version numbers are lower than the
  internal version number by 11.
 

 

Questions or comments are always welcome!