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

[Jan Hubicka]

> 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

I have managed to commit partially, it should be fixed now.  My apologizes for this!

Honza
> 
> -- 
> H.J.