[PATCH] D82733: [clang][docs] Add note about using `-flto` with `-g` on macOS

[Philippe Blain via Phabricator via cfe-commits]

phil-blain updated this revision to Diff 274286.
phil-blain added a comment.

Use `note::` Sphinx directive

Also:

- Fix Sphinx formatting for preformatted text
- Correctly pass the linker argument (initial '-' was missing)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D82733/new/

https://reviews.llvm.org/D82733

Files:
  clang/docs/CommandGuide/clang.rst


Index: clang/docs/CommandGuide/clang.rst
===================================================================
--- clang/docs/CommandGuide/clang.rst
+++ clang/docs/CommandGuide/clang.rst
@@ -474,6 +474,16 @@
   optimization. With "thin", :doc:`ThinLTO <../ThinLTO>`
   compilation is invoked instead.
 
+  .. note::
+
+     On Darwin, when using :option:`-flto` along with :option:`-g` and
+     compiling and linking in separate steps, you also need to pass
+     ``-Wl,-object_path_lto,<lto-filename>.o`` at the linking step to instruct the
+     ld64 linker not to delete the temporary object file generated during Link
+     Time Optimization (this flag is automatically passed to the linker by Clang
+     if compilation and linking are done in a single step). This allows debugging
+     the executable as well as generating the ``.dSYM`` bundle using :manpage:`dsymutil(1)`.
+
 Driver Options
 ~~~~~~~~~~~~~~
 


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