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.
The ENABLE_EXPORTS property exports all symbols from executables on
UNIX-like platforms, typically for use by plugins. Honor this behavior
on Cygwin. See issue #10122.
In commit "use export all symbols on cygwin" (2003-01-21) we started
passing -Wl,--export-all-symbols when linking shared libraries. Now
cygwin exports all symbols automatically if no symbols are explicitly
exported. When symbols are explicitly exported we want to honor that
narrow interface. Therefore this flag should not be passed.
Change based on patch from issue #10122.
The variable should contain the name of a library needed to link the
symbol equivalent to dlopen. On Cygwin no special library is needed,
and certainly not "gdi32".
Change based on patch from issue #10122.
This moves GNU compiler flags into new-style modules
Compiler/GNU-<lang>.cmake
Platform/<os>-GNU-<lang>.cmake
We use language-independent helper modules
Compiler/GNU.cmake
Platform/<os>-GNU.cmake
to define macros consolidating the information.
Stephen Kelly
Bill Hoffman
Todd Gamblin
Yaakov Selkowitz
Brad King