[PATCH 1/1] build/cmake: Fix CMP0023 warning with libffi

[Dan Liew]

Hi Jan,

>> anything wrong with this patch?

I'm CC'ing Brad King because he is much more of an expert on CMake
than I am. I'll try to take a look though...

>> >  if( LLVM_ENABLE_FFI )
>> > -  target_link_libraries( LLVMInterpreter ${FFI_LIBRARY_PATH} )
>> > +  target_link_libraries( LLVMInterpreter ${cmake_2_8_12_PRIVATE} ${FFI_LIBRARY_PATH} )
>> >  endif()

Shouldn't you be using ${cmake_2_8_12_INTERFACE} rather than
${cmake_2_8_12_PRIVATE}? If you build using libffi presumably any
client of LLVM using the interpreter needs to link against it too
hence this library should end up in INTERFACE_LINK_LIBRARIES (which
using INTERFACE in target_link_libraries will achieve)? Also seeing as
libLLVMInterpreter.a is a static library linking against libffi
doesn't make sense which is what PRIVATE does (AFAICT).

However I may of misunderstood the meaning of the PUBLIC, PRIVATE and
INTERFACE keywords because I've never used them before and I'm my
understanding comes from just glancing at the cmake documentation.