Re: [RFA] Incremental LTO linking part 1: simple-object bits

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, May 8, 2018 at 8:05 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
> Hi,
> for incremental linking of LTO objects we need to copy debug sections from
> source object files into destination without renaming them from .gnu.debuglto
> into the standard debug section (because they will again be LTO debug section
> in the resulting object file).
>
> I have discussed this with Richard on IRC and I hope it is fine to change the
> API here becuase lto-wrapper is the only user of this function.  I will send
> lto-wrapper support in separate patch.
>
> I have lto-bootstrapped/regtested the whole incremental linking patchet on
> x86-64-linux with libbackend being incrementaly linked and also experimented
> with extra testcases and tested that debugging works on resulting cc1 binary.
> OK?
>
> Honza
>
>         * simple-object.h (simple_object_copy_lto_debug_sections): Add rename
>         parameter.
>         * simple-object.c (handle_lto_debug_sections): Add rename parameter.
>         (handle_lto_debug_sections_rename): New function.
>         (handle_lto_debug_sections_norename): New function.
>         (simple_object_copy_lto_debug_sections): Add rename parameter.
> Index: include/simple-object.h
> ===================================================================
> --- include/simple-object.h     (revision 260042)
> +++ include/simple-object.h     (working copy)
> @@ -198,12 +198,15 @@
>  simple_object_release_write (simple_object_write *);
>
>  /* Copy LTO debug sections from SRC_OBJECT to DEST.
> +   If RENAME is true, rename LTO debug section into debug section (i.e.
> +   when producing final binary) and if it is false, keep the sections with
> +   original names (when incrementally linking).
>     If an error occurs, return the errno value in ERR and an error string.  */
>
>  extern const char *
>  simple_object_copy_lto_debug_sections (simple_object_read *src_object,
>                                        const char *dest,
> -                                      int *err);
> +                                      int *err, int rename);
>
>  #ifdef __cplusplus
>  }

This part is missing from r260956:

https://gcc.gnu.org/ml/gcc-cvs/2018-05/msg01177.html

-- 
H.J.