Specify unwind lib before other system libraries.

[ychen]

Summary

This matters on OSX because static linking orders is also the order dyld uses to search for libs(the default - Two-level namespace).
If system libs (including unwind lib) are specified before local unwind lib, local unwind lib would never be picked up by dyld.

Before
$ otool -L lib/libc++abi.dylib
lib/libc++abi.dylib:

@rpath/libc++abi.1.dylib (compatibility version 1.0.0, current version 1.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1252.200.5)
@rpath/libunwind.1.dylib (compatibility version 1.0.0, current version 1.0.0)

After
$ otool -L lib/libc++abi.dylib
lib/libc++abi.dylib:

@rpath/libc++abi.1.dylib (compatibility version 1.0.0, current version 1.0.0)
@rpath/libunwind.1.dylib (compatibility version 1.0.0, current version 1.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1252.200.5)

[phosek]

src/CMakeLists.txt

229 ↗

(On Diff #184445)

Can you also update this line for (visual) consistency?

[ychen]

• also change static lib linking order for consistency

[ychen]

address comment

[phosek]

LGTM

[ychen]

Could you please commit this for me? Thank you!

[ldionne]

Sorry for the delay. Can you please rebase this on top of the current master? I am unable to apply the patch for some reason.

[ychen]

• rebase

libcxxabi/trunk/src/CMakeLists.txt

 endif()
 
 # Build the shared library.
 if (LIBCXXABI_ENABLE_SHARED)
   add_library(cxxabi_shared SHARED ${cxxabi_shared_sources})
   if(COMMAND llvm_setup_rpath)
     llvm_setup_rpath(cxxabi_shared)
   endif()
-  target_link_libraries(cxxabi_shared PRIVATE ${LIBCXXABI_LIBRARIES} ${LIBCXXABI_SHARED_LIBRARIES})
+  target_link_libraries(cxxabi_shared PRIVATE ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
   set_target_properties(cxxabi_shared
                         PROPERTIES
                           CXX_EXTENSIONS
                             OFF
                           CXX_STANDARD
                             11
                           CXX_STANDARD_REQUIRED
                             ON
if (TARGET unwind_static OR HAVE_LIBUNWIND)
       if(LIBUNWIND_HERMETIC_STATIC_LIBRARY)
         list(APPEND cxxabi_static_sources $<TARGET_OBJECTS:unwind_static_objects>)
       else()
         list(APPEND cxxabi_static_sources $<TARGET_OBJECTS:unwind_objects>)
       endif()
     endif()
   endif()
   add_library(cxxabi_static STATIC ${cxxabi_static_sources})
-  target_link_libraries(cxxabi_static PRIVATE ${LIBCXXABI_LIBRARIES} ${LIBCXXABI_STATIC_LIBRARIES})
+  target_link_libraries(cxxabi_static PRIVATE ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
   set_target_properties(cxxabi_static
                         PROPERTIES
                           CXX_EXTENSIONS
                             OFF
                           CXX_STANDARD
                             11
                           CXX_STANDARD_REQUIRED
                             ON