[Bug lto/67548] [5/6 Regression] LTO drops weak binding with "ld -r"

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67548

--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Jan Hubicka from comment #5)
> > None of them is applicable to a weakdef with "ld -r".
> Yep, GCC simply assumes that incremental linking is not going to happen and
> it makes strong assumptions
> about visibility in static&PIC binaries.
> To support incremental linking we need a way to pass this information to
> GCC. Either by extra codes or
> by informing the plugin that linking is incremental.
> See also https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64860
> 
> Honza

Linker passes this

/* The type of output file being generated by the linker.  */

enum ld_plugin_output_file_type
{
  LDPO_REL,
  LDPO_EXEC,
  LDPO_DYN,
  LDPO_PIE
};

to GCC plug-in.  But this information is never used by GCC plug-in.