# CMake 3.17 Release Notes

Changes made since CMake 3.16 include the following.

## New Features

### Generators

- `cmake(1)` gained a `Ninja Multi-Config` generator, which is similar to the `Ninja` generator but can be used to build multiple configurations at once.

- Visual Studio Generators learned to support per-config sources. Previously only Command-Line Build Tool Generators supported them.

- Visual Studio Generators for VS 2010 and above now support specifying the `VCTargetsPath` value for project files in `CMAKE_GENERATOR_TOOLSET` setting.

- Visual Studio Generators for VS 2010 and above learned to support .NET Standard and .NET Core. See the `DOTNET_TARGET_FRAMEWORK` target property and associated `CMAKE_DOTNET_TARGET_FRAMEWORK` variable.

### Languages

- The `Compile Features` functionality now offers meta-features for the CUDA language standard levels (e.g. `cuda_std_03`, `cuda_std_14`). See `CMAKE_CUDA_KNOWN_FEATURES`.

### Compilers

- The IBM XL Fortran compiler is now supported by the `Ninja` generator.

### Command-Line

- `cmake(1)` gained a `--debug-find` command-line option to enable additional human-readable output on where `find_*` commands search.

- `cmake(1)` gained a `--trace-format` command-line option that can be used to set the `--trace` output format. Currently, the old human readable and the new JSON format are supported. The new JSON format is easier to parse automatically than the existing format.

- `cmake(1)` gained a `-E rm` command-line tool that can be used to remove directories and files. This supersedes the existing `-E remove` and `-E remove_directory` tools and has better semantics.

### Commands

- The `add_custom_command()` command learned to interpret paths in `DEPENDS` arguments that are specified relative to the current binary directory.

- The `foreach()` command learned a new `ZIP_LISTS` option to iterate over multiple lists simultaneously.

- The `load_cache(READ_WITH_PREFIX)` command mode is now allowed when using `cmake -P` to Run a Script.

- The `message()` command learned to output context provided in the `CMAKE_MESSAGE_CONTEXT` variable for log levels `NOTICE` and below. Enable this output with the new `--log-context` command-line option or `CMAKE_MESSAGE_CONTEXT_SHOW` variable.

- The `message()` command gained new keywords `CHECK_START`, `CHECK_PASS` and `CHECK_FAIL`.

- The `target_compile_options()` command now honors the `BEFORE` keyword more consistently. See policy `CMP0101`.

### Variables

- A `CMAKE_CTEST_ARGUMENTS` variable was added to specify a list of command-line arguments passed to CTest when running through the `test` (or `RUN_TESTS`) target of the generated build system.

- The following variables are now defined inside a `function()`:

  - `CMAKE_CURRENT_FUNCTION`

  - `CMAKE_CURRENT_FUNCTION_LIST_DIR`

  - `CMAKE_CURRENT_FUNCTION_LIST_FILE`

  - `CMAKE_CURRENT_FUNCTION_LIST_LINE`

- The `CMAKE_CUDA_RUNTIME_LIBRARY` variable and `CUDA_RUNTIME_LIBRARY` target property were introduced to select the CUDA runtime library used when linking targets that use CUDA.

- The `CMAKE_FIND_DEBUG_MODE` variable was introduced to print extra `find_*` call information during the cmake run to standard error. Output is designed for human consumption and not for parsing.

- The `CMAKE_EXPORT_COMPILE_COMMANDS` variable now takes its initial value from the `CMAKE_EXPORT_COMPILE_COMMANDS` environment variable if no explicit configuration is given.

- The `CMAKE_<LANG>_COMPILER_LAUNCHER` variable, if not set explicitly, now takes its initial value from the `CMAKE_<LANG>_COMPILER_LAUNCHER` environment variable.

- The `CMAKE_MESSAGE_LOG_LEVEL` variable can now be used to persist a log level between CMake runs, unlike the `--log-level` command line option which only applies to that particular run.

- The `CMAKE_XCODE_SCHEME_ENVIRONMENT` variable was added to initialize the `XCODE_SCHEME_ENVIRONMENT` target property.

- The `CMAKE_XCODE_SCHEME_WORKING_DIRECTORY` variable and associated `XCODE_SCHEME_WORKING_DIRECTORY` target property were added to tell the `Xcode` generator to set the value of the `Custom Working Directory` schema option.

### Properties

- The `AIX_EXPORT_ALL_SYMBOLS` target property and associated `CMAKE_AIX_EXPORT_ALL_SYMBOLS` variable were created to optionally explicitly disable automatic export of symbols from shared libraries on AIX.

- The `DEPRECATION` target property was added to mark a target as deprecated. If a linked target is marked as deprecated, a warning with the deprecation message is issued at generate time.

- The `INSTALL_NAME_DIR` target property now supports `generator expressions`. In particular, the `$<INSTALL_PREFIX>` generator expression can be used to set the directory relative to the install-time prefix.

- Target properties `MACHO_COMPATIBILITY_VERSION` and `MACHO_CURRENT_VERSION` were added to set the `compatibility_version` and `curent_version`, respectively, for Mach-O binaries. For backwards compatibility, if these properties are not set, `SOVERSION` and `VERSION` are used respectively as fallbacks.

- The `VS_DOTNET_DOCUMENTATION_FILE` target property was added to tell Visual Studio Generators to generate a `DocumentationFile` reference in `.csproj` files.

### Modules

- The `ExternalProject` module `ExternalProject_Add()` command gained a `GIT_SUBMODULES_RECURSE` option to specify whether Git submodules should be updated recursively. The default is on to preserve existing behavior.

- The `FindCUDAToolkit` module was added to find the CUDA Toolkit without enabling CUDA as a language.

- The `FindCURL` module learned to find CURL using the `CURLConfig.cmake` package configuration file generated by CURL's cmake buildsystem. It also gained a new `CURL_NO_CURL_CMAKE` option to disable this behavior.

- The `FindFLEX` module's `FLEX_TARGET` command now runs `flex` with `CMAKE_CURRENT_BINARY_DIR` as the working directory. See policy `CMP0098`.

- The `FindLibArchive` module now provides an imported target for libarchive.

- The `FindPython` module has learned to find Python components in active virtual environments managed by `conda`.

- The `FindPython3` and `FindPython` modules gained, respectively, variable `Python3_SOABI` and `Python_SOABI` giving the standard extension suffix for modules. Moreover, commands `Python3_add_library()` and `Python_add_library()` gained the option `WITH_SOABI` to prefix the library suffix with the value of `SOABI`.

- The `FindLibXml2` module now provides an imported target for the `xmllint` executable.

### Autogen

- `AUTOMOC` and `AUTOUIC` learned to process headers with a `.hh` extension. See policy `CMP0100`.

### CTest

- The `CTEST_CONFIGURATION_TYPE` variable is now set from the command line when `ctest(1)` is invoked with `-C <cfg>`.

- The `ctest(1)` tool gained support for Dr. Memory to run memcheck runs.

- The `ctest(1)` tool gained a `--no-tests=<[error|ignore]>` option to explicitly set and unify the behavior between direct invocation and script mode if no tests were found.

- The `ctest(1)` tool gained a `--repeat <mode>:<n>` option to specify conditions in which to repeat tests. This generalizes the existing `--repeat-until-fail <n>` option to add modes for `until-pass` and `after-timeout`.

- The `ctest_test()` command gained a `REPEAT <mode>:<n>` option to specify conditions in which to repeat tests.

### CPack

- The `CPack DragNDrop Generator` learned to use the `CPACK_DMG_<component>_FILE_NAME` variable to set a custom filename when packaging components into their own DMGs.

- The `CPack DragNDrop Generator` learned to handle RTF formatted license files. When `CPACK_DMG_SLA_DIR` variable is set, `<language>.license.rtf` is considered, but only as a fallback when the plaintext (`.txt`) file is not found in order to maintain backwards compatibility.

- The `CPack NSIS Generator` gained a new variable `CPACK_NSIS_MUI_HEADERIMAGE` to set the header image. To not break existing setups, it still defaults to `CPACK_PACKAGE_ICON` if the new variable is not set.

- The `CPack NSIS Generator` now supports `CPACK_NSIS_UNINSTALL_NAME`. This can be used to specify the name of the Uninstall program.

- The `CPack NSIS Generator` now supports `CPACK_NSIS_WELCOME_TITLE` and `CPACK_NSIS_WELCOME_TITLE_3LINES`. These can be used to specify the welcome page title and display it in 3 lines.

- The `CPack NSIS Generator` now supports `CPACK_NSIS_FINISH_TITLE` and `CPACK_NSIS_FINISH_TITLE_3LINES`. These can be used to specify the finish page title and display it in 3 lines.

- The `CPack productbuild Generator` gained support for a `CPACK_PRODUCTBUILD_BACKGROUND` variable to specify a background image for the macOS installer.

### Other

- `ccmake(1)` now displays cache values using colors based on the entry type if the terminal supports color.

- `ccmake(1)` now displays messages and a progress bar during configure and generate. It will keep the output displayed if any errors or warnings occurred.

## Deprecated and Removed Features

- An explicit deprecation diagnostic was added for policy `CMP0068` and policy `CMP0069` (`CMP0067` and below were already deprecated). The `cmake-policies(7)` manual explains that the OLD behaviors of all policies are deprecated and that projects should port to the NEW behaviors.

- The CPack `PackageMaker` generator has been deprecated because Xcode no longer distributes the PackageMaker tools. The undocumented `OSXX11` generator has also been deprecated.

- The `cmake(1)` command-line `-E remove` and `-E remove_directory` tools are deprecated in favor of the new `-E rm` tool. The older tools always returned 0 if a named path did not exist even without the force option and cannot be fixed without breaking compatibility, and so have been superseded.

- The `CPack NSIS Generator` now requires NSIS 3.0 or later.

## Other Changes

- The `file API` index file now emits a `multiConfig` flag specifying whether or not the generator supports multiple output configurations.

- Target link properties `INTERFACE_LINK_OPTIONS`, `INTERFACE_LINK_DIRECTORIES` and `INTERFACE_LINK_DEPENDS` are now transitive over private dependencies on static libraries. See policy `CMP0099`.

- When using MinGW tools, the `find_library()` command no longer finds `.dll` files by default. Instead, it expects `.dll.a` import libraries to be available.

- The `MinGW Makefiles` generator no longer issues an error if `sh.exe` is present in the environment's `PATH`.

- The `Ninja` generator now prefers the first ninja build tool to appear in the `PATH` no matter whether it is called `ninja-build`, `ninja`, or `samu`. Previously the first of those names to appear anywhere in the `PATH` would be preferred.

- With SDCC the `sdar` tool is now preferred over `sdcclib` as librarian. The latter was deprecated by SDCC 3.2.0 and removed in SDCC 3.8.6.

- With SDCC the default flags no longer include any target-specific flags. Previously the default flags were hard-coded for 8051.

- The `CMAKE_VS_GLOBALS` variable value now applies during compiler identification and in targets created by the `add_custom_target()` command.

- The `Xcode` generator no longer hard-codes `-Wmost`, `-Wno-four-char-constants`, and `-Wno-unknown-pragmas` warning flags.

## Updates

Changes made since CMake 3.17.0 include the following.

### 3.17.1

- CMake 3.17.0 updated the `CPack NSIS Generator` with changes that require NSIS 3.0 or later. CMake 3.17.1 now enforces the use of a sufficiently new version.

### 3.17.3

- Selection of the Objective C or C++ compiler now considers the `CC` or `CXX` environment variable if the `OBJC` or `OBJCXX` environment variable is not set.

- The `FindPkgConfig` module now extracts include directories prefixed with `-isystem` into the `*_INCLUDE_DIRS` variables and `INTERFACE_INCLUDE_DIRECTORIES` target properties. Previously they would be places in `*_CFLAGS_OTHER` variables and `INTERFACE_COMPILE_OPTIONS` target properties.

### 3.17.5

- The default value of `CMAKE_AUTOMOC_PATH_PREFIX` was changed to `OFF` because this feature can break existing projects that have identically named header files in different include directories. This restores compatibility with behavior of CMake 3.15 and below. The default was also changed to `OFF` in 3.16.9.