Add a feature test using the compiler macros and the preprocessor to
determine available features.
Add a CMAKE_CXX_COMPILE_FEATURES variable which contains all features
known to the loaded compiler, and a CMAKE_CXX_KNOWN_FEATURES variable
containing all features known to CMake. Add language standard specific
variables for internal use to determine the standard-specific compile
flags to use.
This will be extended to other languages in the future. Follow-up
commits will add features which will be recorded by the feature test.
These policies are triggered by the use of a particular compiler rather
than outdated CMake code in a project. Avoid warning in every project
that enables a language by not displaying the policy warning by default.
Add variable CMAKE_POLICY_WARNING_CMP<NNNN> to control the warning
explicitly; otherwise enable the warning with --debug-output or --trace.
This breaks with strict policy convention because it does not provide
developers with any warning about the behavior change by default.
Existing projects will continue to build without a warning or change in
behavior. When a developer changes the minimum required version of
CMake in a project to a sufficiently high value (3.0), the project will
suddenly get the new compiler id and may break, but at least the
breakage comes with a change to the project rather than the version of
CMake used to build it.
Breaking strict policy convention is worthwhile in this case because
very few projects will be affected by the behavior change but every
project would have to see the warning if it were enabled by default.
Since commit v2.8.12~437^2~2 (VS: Separate compiler and linker PDB files
2013-04-05) we no longer set /Fd with the PDB_NAME or PDB_OUTPUT_DIRECTORY
properties. Those properties now exclusively handle linker PDB files.
Since STATIC libraries do not link their compiler PDB file becomes more
important. Add new target properties "COMPILE_PDB_NAME[_<CONFIG>]" and
"COMPILE_PDB_OUTPUT_DIRECTORY[_<CONFIG>]" to specify the compiler PDB
file location and pass the value to the MSVC /Fd option.
Teach the project() command to set variables
{PROJECT,<PROJECT-NAME>}_VERSION{,_MAJOR,_MINOR,_PATCH,_TWEAK}
holding the project version number and its components. Add project()
command option "VERSION" to specify the version explicitly, and default
to the empty string when it is not given.
Since this clears variables when no VERSION is given, this may change
behavior for existing projects that set the version variables themselves
prior to calling project(). Add policy CMP0048 for compatibility.
Suggested-by: Alex Neundorf <neundorf@kde.org>
Add documentation entries for variables
CMAKE_OSX_ARCHITECTURES
CMAKE_OSX_DEPLOYMENT_TARGET
CMAKE_OSX_SYSROOT
Explain what each does and when/how they should be set.
Since commit 5f5c92b9 (VS: Add internal APIs to find MSBuild,
devenv/VCExpress, and msdev, 2013-11-13) the VS generators have
known how to lookup the locations of their build tools directly.
Expose this information to CMake language code by defining new
variables to hold the paths to these tools.
This variable can be useful in cross-compiling contexts where the
sysroot is read-only or where the sysroot should otherwise remain
pristine.
If the new CMAKE_STAGING_PREFIX variable is set, it is used instead
of CMAKE_INSTALL_PREFIX when generating the installation rules in
cmake_install.cmake.
This way, the CMAKE_INSTALL_PREFIX variable
always refers to the installation prefix on the target device, regardless
of whether host==target.
If any -rpath paths passed to the linker contain the CMAKE_STAGING_PREFIX,
the matching path fragments are replaced with the CMAKE_INSTALL_PREFIX.
Matching paths in the -rpath-link are not transformed.
The cross-prefix usr-move workaround is assumed not to require extension
regarding CMAKE_STAGING_PREFIX. The staging area is a single prefix, so
there is no scope for cross-prefix symlinks. The CMAKE_INSTALL_PREFIX
is still used to determine the workaround path, and that variable
remains the relevant one even if CMAKE_STAGING_PREFIX is used. If the
generated export files are deployed to the target, the workaround
will still be in place, and still be employed if required.
As CMAKE_ROOT_FIND_PATH can be a list, a new CMAKE_SYSROOT is
introduced, which is never a list.
The contents of this variable is passed to supporting compilers
as --sysroot. It is also accounted for when processing implicit
link directories reported by the compiler, and when generating
RPATH information.
Clang can compile code, but uses the gcc tools for other tasks such
as linking. The -gcc-toolchain option can be used for that, but
generalize so that other compilers can be treated the same.
If such a location is specified, use it as a hint for finding
the binutils executables.
For clang, this allows passing -target <triple> to the compiler, and
for qcc, -V<arch> using toolchain files containing something like
set(triple arm-linux-gnueabihf)
set(CMAKE_C_COMPILER "/usr/bin/clang")
set(CMAKE_C_COMPILER_TARGET ${triple})
set(CMAKE_CXX_COMPILER "/usr/bin/clang++")
set(CMAKE_CXX_COMPILER_TARGET ${triple})
or
set(arch gcc_ntoarmv7le)
set(CMAKE_C_COMPILER /opt/qnx650/host/linux/x86/usr/bin/qcc)
set(CMAKE_C_COMPILER_TARGET ${arch})
set(CMAKE_CXX_COMPILER /opt/qnx650/host/linux/x86/usr/bin/QCC)
set(CMAKE_CXX_COMPILER_TARGET ${arch})
Both clang and qcc are inherently cross compiler( driver)s.
When cross-compiling with clang, use the CMAKE_${lang}_COMPILER_TARGET
as the _CMAKE_TOOLCHAIN_PREFIX to find the appropriate binutils.
When cross-compiling with QNX qcc, use the CMAKE_${lang}_COMPILER_TARGET
to set the appropriate _CMAKE_TOOLCHAIN_PREFIX.
Add a :maxdepth: option to all toctree directives to limit their depth
to 1. We do not want subheadings from individual documents to pollute
the already large lists of CMake Domain objects.
In certain scenarios, it is preferable to keep a 'dirty' install prefix
than to clear it, and to expect that content will not be found there.
Add a CMAKE_FIND_NO_INSTALL_PREFIX variable that can be set to disable
searching the install prefix.
Add the man page description line as explicit markup at the top of each
Help/manual/*.rst file and scan it from conf.py to automatically
generate the man_pages Sphinx configuration value. This reduces the
number of places that need to be changed when a new manual is added.
The source files are already processed by cmQtAutomoc to look for
moc includes, so extend that to also look for ui_ includes and
find corresponding .ui files to process.
This replaces the need to invoke qt4_wrap_ui().
As the ui files are not likely to be part of the SOURCES of the
target, store the options associated with them separately in the
cmMakefile for querying during the autogen run.
Lookup the Intel VS plugin version on demand in the VS global generator,
compute the corresponding .vfproj format version number, and memoize it.
Add it as a CMAKE_VS_INTEL_Fortran_PROJECT_VERSION platform definition.