Add dependency on clang-headers when building LLDB.framework using CMake

[xiaobai]

Summary

The LLDB.framework generated when building with CMake + Ninja/Make is
completely missing the clang headers. Although the code to copy them exists, we
don't even generate them unless we're building LLDB standalone.

[labath]

I don't understand the interactions between lldb framework and clang headers, but if there isn't a better person to review this, I'm happy to rubber-stamp it. :)

[xiaobai]

In D47612#1118615, @labath wrote:

I don't understand the interactions between lldb framework and clang headers, but if there isn't a better person to review this, I'm happy to rubber-stamp it. :)

Thanks! I don't quite understand it either, but I am trying to make it so we can build the LLDB framework with just CMake+Make/Ninja. :)

lldb/trunk/source/API/CMakeLists.txt

if(LLDB_BUILD_FRAMEWORK)
   set_target_properties(liblldb PROPERTIES
     OUTPUT_NAME LLDB
     FRAMEWORK On
     FRAMEWORK_VERSION ${LLDB_FRAMEWORK_VERSION}
     LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${LLDB_FRAMEWORK_INSTALL_DIR}
     PUBLIC_HEADER "${framework_headers}")
 
   if(NOT IOS)
+    if (NOT LLDB_BUILT_STANDALONE)
+      add_dependencies(liblldb clang-headers)
+    endif()
     add_custom_command(TARGET liblldb POST_BUILD
       COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_CURRENT_BINARY_DIR}/FrameworkHeaders $<TARGET_FILE_DIR:liblldb>/Headers
       COMMAND ${CMAKE_COMMAND} -E create_symlink Versions/Current/Headers ${CMAKE_BINARY_DIR}/${LLDB_FRAMEWORK_INSTALL_DIR}/LLDB.framework/Headers
       COMMAND ${CMAKE_COMMAND} -E create_symlink ${LLDB_FRAMEWORK_VERSION} ${CMAKE_BINARY_DIR}/${LLDB_FRAMEWORK_INSTALL_DIR}/LLDB.framework/Versions/Current
       COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/clang/${LLDB_VERSION} $<TARGET_FILE_DIR:liblldb>/Resources/Clang
       )
   else()
     add_custom_command(TARGET liblldb POST_BUILD
       COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_CURRENT_BINARY_DIR}/FrameworkHeaders $<TARGET_FILE_DIR:liblldb>/Headers
       )
   endif()
 
 endif()