[cmake] Generate symbol exports files in config subdir

[Ilod]

Summary

When generating native symbols export files, these files are generated in CMAKE_CURRENT_BINARY_DIR. However, on multi-configuration build-systems, such as Xcode and MSVC, this folder is shared between all configurations.
On this case, switching configuration may make the build system think the file is up-to-date, and use the file from the other configuration (resulting in link error if referencing symbol no longer existing because of inlining, or in non-exported symbols in the reverse case).

This patch generate the files in the CMAKE_CFG_INTDIR subfolder, to have a different file for each configuration.

[john.brawn]

LGTM.

[Ilod]

I don't have commit rights, so I'll be dependent of someone commiting it for me.

cmake/modules/AddLLVM.cmake

set_property(TARGET ${name} APPEND_STRING PROPERTY
       COMPILE_FLAGS "${target_compile_flags}")
   endif()
 
   set_property(TARGET ${name} APPEND PROPERTY COMPILE_DEFINITIONS ${LLVM_COMPILE_DEFINITIONS})
 endfunction()
 
 function(add_llvm_symbol_exports target_name export_file)
   if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-    set(native_export_file "${target_name}.exports")
+    set(native_export_file "${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${target_name}.exports")
     add_custom_command(OUTPUT ${native_export_file}
       COMMAND sed -e "s/^/_/" < ${export_file} > ${native_export_file}
       DEPENDS ${export_file}
       VERBATIM
       COMMENT "Creating export file for ${target_name}")
     set_property(TARGET ${target_name} APPEND_STRING PROPERTY
-                 LINK_FLAGS " -Wl,-exported_symbols_list,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+                 LINK_FLAGS " -Wl,-exported_symbols_list,${native_export_file}")
   elseif(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
     set_property(TARGET ${target_name} APPEND_STRING PROPERTY
                  LINK_FLAGS " -Wl,-bE:${export_file}")
   elseif(LLVM_HAVE_LINK_VERSION_SCRIPT)
     # Gold and BFD ld require a version script rather than a plain list.
-    set(native_export_file "${target_name}.exports")
+    set(native_export_file "${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${target_name}.exports")
     # FIXME: Don't write the "local:" line on OpenBSD.
     add_custom_command(OUTPUT ${native_export_file}
       COMMAND echo "{" > ${native_export_file}
       COMMAND grep -q "[[:alnum:]]" ${export_file} && echo "  global:" >> ${native_export_file} || :
       COMMAND sed -e "s/$/;/" -e "s/^/    /" < ${export_file} >> ${native_export_file}
       COMMAND echo "  local: *;" >> ${native_export_file}
       COMMAND echo "};" >> ${native_export_file}
       DEPENDS ${export_file}
       VERBATIM
       COMMENT "Creating export file for ${target_name}")
     if (${CMAKE_SYSTEM_NAME} MATCHES "SunOS")
       set_property(TARGET ${target_name} APPEND_STRING PROPERTY
-                   LINK_FLAGS "  -Wl,-M,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+                   LINK_FLAGS "  -Wl,-M,${native_export_file}")
     else()
       set_property(TARGET ${target_name} APPEND_STRING PROPERTY
-                   LINK_FLAGS "  -Wl,--version-script,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+                   LINK_FLAGS "  -Wl,--version-script,${native_export_file}")
     endif()
   else()
-    set(native_export_file "${target_name}.def")
+    set(native_export_file "${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${target_name}.def")
 
     add_custom_command(OUTPUT ${native_export_file}
       COMMAND ${PYTHON_EXECUTABLE} -c "import sys;print(''.join(['EXPORTS\\n']+sys.stdin.readlines(),))"
         < ${export_file} > ${native_export_file}
       DEPENDS ${export_file}
       VERBATIM
       COMMENT "Creating export file for ${target_name}")
-    set(export_file_linker_flag "${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+    set(export_file_linker_flag "${native_export_file}")
     if(MSVC)
       set(export_file_linker_flag "/DEF:\"${export_file_linker_flag}\"")
     endif()
     set_property(TARGET ${target_name} APPEND_STRING PROPERTY
                  LINK_FLAGS " ${export_file_linker_flag}")
   endif()
 
   add_custom_target(${target_name}_exports DEPENDS ${native_export_file})