Store in new platform variables
CMAKE_${lang}_COMPILE_OPTIONS_PIC
CMAKE_${lang}_COMPILE_OPTIONS_PIE
flags for position independent code generation.
In almost all cases, this means duplication of the
CMAKE_SHARED_LIBRARY_${lang}_FLAGS for the _PIC case and using the
assumed pie equivalent for the _PIE case. Note that the GNU compiler
has supported -fPIE since 3.4 and that there is no -fPIC on GNU for
Windows or Cygwin.
There is a possibility that the _PIE variables are not correct.
However, as there is no backwards compatibility to be concerned about
(as the POSITION_INDEPENDENT_CODE property is not used anywhere yet),
the current state suffices.
Several platform-wide linker flag variables are defined in
Modules/Platform/<os>.cmake files for C and then copied by the
Modules/CMake<lang>Information.cmake file for each language.
We now use this approach for the variables
CMAKE_EXE_EXPORTS_${lang}_FLAG
CMAKE_SHARED_LIBRARY_SONAME_${lang}_FLAG
CMAKE_SHARED_LIBRARY_CREATE_${lang}_FLAGS
to avoid duplication for multiple languages in each platform file.
- 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
Stephen Kelly
Brad King
Bill Hoffman