In CMake 2.4 the generated link line for a target always preserved the
originally specified libraries in their original order. Dependencies
were satisfied by inserting extra libraries into the line, though it had
some bugs. In CMake 2.6.0 we preserved only the items on the link line
that are not known to be shared libraries. This reduced excess
libraries on the link line. However, since we link to system libraries
(such as /usr/lib/libm.so) by asking the linker to search (-lm), some
linkers secretly replace the library with a static library in another
implicit search directory (developers can override this by using an
imported target to force linking by full path). When this happens the
order still matters.
To avoid this and other potential subtle issues this commit restores
preservation of all non-target items and static library targets. This
will create cases of unnecessary, duplicate shared libraries on the link
line if the user specifies them, but at least it will work. In the
future we can attempt a more advanced analysis to safely remove
duplicate shared libraries from the link line.
We never explicitly specify system library directories in linker or
runtime search paths. Furthermore, libraries in these directories are
always linked by asking the linker to search for them. We need to
generate a warning when explicitly specified search directories contain
files that may hide the system libraries during the search.
This change introduces policy CMP0008 to decide how to treat full path
libraries that do not appear to be valid library file names. Such
libraries worked by accident in the VS IDE and Xcode generators with
CMake 2.4 and below. We support them in CMake 2.6 by introducing this
policy. See policy documentation added by this change for details.
Sometimes we ask the linker to search for a library for which the path
is known but for some reason cannot be specified by full path. In these
cases do not include the library in CMP0003 warnings because we know the
extra paths are not needed for it.
- This case worked accidentally in CMake 2.4, though not in Makefiles.
- Some projects build only with the VS IDE on windows and have this
mistake.
- Support them when 2.4 compatibility is enabled by adding the extension.
- Place the built library in foo.framework/Versions/A/foo
- Do not create unused content symlinks (like PrivateHeaders)
- Do not use VERSION/SOVERSION properties for frameworks
- Make cmTarget::GetDirectory return by value
- Remove the foo.framework part from cmTarget::GetDirectory
- Correct install_name construction and conversion on install
- Fix MACOSX_PACKAGE_LOCATION under Xcode to use the
Versions/<version> directory for frameworks
- Update the Framework test to try these things
- CMake 2.4 added link directories for targets linked
in the optimized configuration even when building debug
- Old behavior for policy CMP0003 must account for this
- Give example code to avoid the warning
- Make explanation more consise
- Explicitly state this is for compatibility
- Issue the warning for at most one target
- Targets built in the tree now add compatibility paths too
- The warning message's first list includes at most one item
for each unique compatibility path
- Clarified error message further
- Policy is WARN by default so projects will build
as they did in 2.4 without user intervention
- Remove CMAKE_LINK_OLD_PATHS variable since it was
never in a release and the policy supercedes it
- Report target creation backtrace in warning message
since policy should be set by that point
- Move computation of extended build-tree rpath
to cmComputeLinkInformation
- Only enable the extended build-tree rpath if
the target will be installed
- Generalize the interface of file(CHRPATH)
- When changing the rpath on installation only
replace the part generated by CMake because
the native tools (ex SunCC on Linux) might have
added their own part to the rpath
- Add cmSystemTools::ChangeRPath method
- Add undocumented file(CHRPATH) command
- When installing use file(CHRPATH) to change the rpath
instead of relinking
- Remove CMAKE_CHRPATH lookup from CMakeFindBinUtils
- Remove CMAKE_USE_CHRPATH option since this should
always work
- Reduce false positives in cases of unknown soname
- Make library extension regular expressions match only at end of string
- When linking to libraries in implicit dirs convert to the -l option
only if the file name is one that can be found by the linker
(ex. /usr/lib/libfoo.so.1 should be linked by full path)
- Add cmSystemTools::GuessLibrarySOName to guess the soname of a
library based on presence of a symlink
- In cmComputeLinkInformation try to guess an soname before assuming
that a third-party library is built without an soname
- In cmOrderDirectories guess the soname of shared libraries in cases
it is otherwise unknown
- Use linker search path -L.. -lfoo for lib w/out soname
when platform sets CMAKE_PLATFORM_USES_PATH_WHEN_NO_SONAME
- Rename cmOrderRuntimeDirectories to cmOrderDirectories
and generalize it for both soname constraints and link
library constraints
- Use cmOrderDirectories to order -L directories based
on all needed constraints
- Avoid processing implicit link directories
- For CMAKE_OLD_LINK_PATHS add constraints from libs
producing them to produce old ordering
- Move runtime path ordering out of cmComputeLinkInformation
into its own class cmOrderRuntimeDirectories.
- Create an instance of cmOrderRuntimeDirectories for runtime
path ordering and another instance for dependent library
path ordering.
- Replace CMAKE_DEPENDENT_SHARED_LIBRARY_MODE with explicit
CMAKE_LINK_DEPENDENT_LIBRARY_FILES boolean.
- Create CMAKE_LINK_DEPENDENT_LIBRARY_DIRS boolean.
- Create variables to specify -rpath-link flags:
CMAKE_SHARED_LIBRARY_RPATH_LINK_<LANG>_FLAG
CMAKE_EXECUTABLE_RPATH_LINK_<LANG>_FLAG
- Enable -rpath-link flag on Linux and QNX.
- Documentation and error message updates
- Split IMPORTED_LINK_LIBRARIES into two parts:
IMPORTED_LINK_INTERFACE_LIBRARIES
IMPORTED_LINK_DEPENDENT_LIBRARIES
- Add CMAKE_DEPENDENT_SHARED_LIBRARY_MODE to select behavior
- Set mode to LINK for Darwin (fixes universal binary problem)
- Update ExportImport test to account for changes
- Imported frameworks have the FRAMEWORK property set
- Added cmTarget::IsFrameworkOnApple method to simplify checks
- Also remove separate IMPORTED_ENABLE_EXPORTS property and just use ENABLE_EXPORTS since, like FRAMEWORK, it just represents the target type.
- Document FRAMEWORK keyword in INSTALL command.
- Updated IMPORTED_LOCATION property documentation for Frameworks
- Created cmExportFileGenerator hierarchy to implement export file generation
- Installed exports use per-config import files loaded by a central one.
- Include soname of shared libraries in import information
- Renamed PREFIX to NAMESPACE in INSTALL(EXPORT) and EXPORT() commands
- Move addition of CMAKE_INSTALL_PREFIX to destinations to install generators
- Import files compute the installation prefix relative to their location when loaded
- Add mapping of importer configurations to importee configurations
- Rename IMPORT targets to IMPORTED targets to distinguish from windows import libraries
- Scope IMPORTED targets within directories to isolate them
- Place all properties created by import files in the IMPORTED namespace
- Document INSTALL(EXPORT) and EXPORT() commands.
- Document IMPORTED signature of add_executable and add_library
- Enable finding of imported targets in cmComputeLinkDepends
- This will be useful for imported library dependencies
- Replaces old cmTarget analyze-lib-depends stuff for linking
- Formalizes graph construction and dump
- Explicitly represents dependency inferral sets
- Use BFS of initial dependencies to preserve order
- This is purely an implementation improvement. No interface has changed.
- Create cmComputeLinkInformation class
- Move and re-implement logic from:
cmLocalGenerator::ComputeLinkInformation
cmOrderLinkDirectories
- Link libraries to targets with their full path (if it is known)
- Dirs specified with link_directories command still added with -L
- Make link type specific to library names without paths
(name libfoo.a without path becomes -Wl,-Bstatic -lfoo)
- Make directory ordering specific to a runtime path computation feature
(look for conflicting SONAMEs instead of library names)
- Implement proper rpath support on HP-UX and AIX.
Brad King
Bill Hoffman