In the `try_compile` source file signature we propagate the caller's
value of `CMAKE_<LANG>_FLAGS` into the test project. Extend this to
propagate `CMAKE_<LANG>_FLAGS_<CONFIG>` too instead of always using the
default value in the test project. This will be useful, for example, to
allow the MSVC runtime library to be changed (e.g. `-MDd` => `-MTd`).
However, some projects may currently depend on this not being done,
so we need to activate the behavior using a policy.
This change was originally made by commit v3.6.0-rc1~160^2 (try_compile:
Honor CMAKE_<LANG>_FLAGS_<CONFIG> changes, 2016-04-11) but without the
policy and so had to be reverted during the 3.6 release candidate cycle.
Fixes#16174.
In Sphinx output formats that print the toctree the policy numbers in
links from the cmake-policies(7) manual are not descriptive. Convert
the toctree entries to cross-reference syntax and add the summary of
each policy. For now simply duplicate the policy summary line. We
already maintain copies in `cmPolicies.h` and `Help/policy/*.rst` docs.
if(TEST TestNameThatExists) will return true if a test with the name
TestNameThatExists has been added with add_test. The syntax is similar
to if(TARGET TargetName). Since use of "TEST" as an argument to if()
could previously be interpreted as a non-keyword argument, add policy
CMP0064 to treat it as a keyword as NEW behavior.
The most likely documentation page a project author will read in
response to a policy warning is the page for the policy itself.
Add to every policy documentation page a note explicitly stating
that the OLD behavior is deprecated. Also mention this in the
cmake_policy() command documentation that explains how to set a
policy to OLD.
Suggested-by: Fraser Hutchison <fraser.hutchison@gmail.com>
The <LANG>_VISIBILITY_PRESET and VISIBILITY_INLINES_HIDDEN were first
merged in commit v2.8.12~322 (Merge topic 'VISIBILITY_PRESET-property',
2013-06-05) but worked only for shared libraries and executables with
exports. Prior to commit v3.0.0-rc1~581^2 (GenerateExportHeader:
Deprecate add_compiler_export_flags function., 2013-09-02) the
add_compiler_export_flags function was used to add visibility flags to
all targets.
The visibility flags are useful for sources in all target types because
they may be later linked into shared libraries or executables with
exports. Introduce policy CMP0063 to enable them for all target types
while preserving compatibility with existing projects that do not expect
this.
When CMP0003 was first introduced we wanted to link all libraries by
full path. However, some projects had problems on platforms where
find_library would find /usr/lib/libfoo.so when the project really
wanted to link to /usr/lib/<arch>/libfoo.so and had been working by
accident because pre-CMP0003 behavior used -lfoo to link.
We first tried to address that in commit v2.6.0~440 (Teach find_library
to avoid returning library paths in system directories, 2008-01-23) by
returning just "foo" for libraries in implicit link directories. This
caused problems for projects expecting find_library to always return a
full path. We ended up using the solution in commit v2.6.0~366 (...
switch library paths found in implicit link directories to use -l,
2008-01-31). However, the special case for libraries in implicit link
directories has also proven problematic and confusing.
Introduce policy CMP0060 to switch to linking all libraries by full path
even if they are in implicit link directories. Explain in the policy
documentation the factors that led to the original approach and now to
this approach.
Add policy CMP0059 to cover this change. The property has been
deprecated since CMake 2.4 anyway.
This will help clean up cmMakefile -- the DefineFlagsOrig member should
not need to exist.
Add policy CMP0058 to avoid generating 'phony' ninja rules for unknown
custom command dependencies. This requires projects to specify their
custom command byproducts explicitly. With this requirement we no
longer have to assume that unknown custom command dependencies are
generated and can instead simply assume they are source files expected
to exist when the build starts. This is particularly important in
in-source builds. It is also helpful for out-of-source builds to allow
Ninja to diagnose missing files before running custom command rules that
depend on them.
Copy CMAKE_EXE_LINKER_FLAGS into the test project generated by
try_compile, just like we already copy CMAKE_<LANG>_FLAGS.
Add CMake Policy CMP0056 to activate this behavior in a compatible way,
but do not warn by default when the policy is not set since it will
affect all try_compile calls.
Extend the RunCMake.try_compile test with a case covering this behavior
for each policy setting.
Allow directories in the source tree or build tree only if the
install tree is a subdirectory of the source tree or build tree,
as appropriate.
Re-use the test files in the RunCMake.include_directories test
to run in multiple scenarios. Bump the required CMake version
in the test to 3.0 to ensure that the new policy warnings are
emitted correctly.
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>
Introduce policy CMP0047 to control resetting the id for
compatibility.
De-duplicate content in the QNX platform file by including the GNU
one. QNX is a form of GNU platform.
Do not clear CMAKE_SHARED_LIBRARY_${lang}_FLAGS variables. They
are populated again later by the Compiler/GNU.cmake file anyway.
Modify the CMAKE_CXX_COMPILE_OBJECT variable only when the QCC
compiler id is in use, and the language is CXX. Use the QNX
recommended flag for QCC instead of the gcc compatible -x flag.
Populate new module files to handle system includes and depfiles
when using the QCC compiler.
Remove code which unsets the system include and depfiles related
variables. When a GNU driver is used instead of the QCC one, the
appropriate flags will be used. These variables were previously
cleared for lowest-common-denominator compatibility with both
drivers.
Diagnostics which check the sanity of exported include paths
previously skipped over any path containing a generator expression.
Introduce a policy to issue an error message in such cases.
The export files created in the OLD behavior are not usable, because
they contain relative paths or paths to the source or build location
which are not suitable for use on installation. CMake will report an
error on import.
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.
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.