Re: [PATCH] Fix PR target/25758, x86-darwin cannot bootstrap itself

[Mike Stump <mrs at apple dot com>]

On Jan 16, 2006, at 12:17 PM, Andrew Pinski wrote:
> The problem here is we are not marking a function as needed so we  
> don't emit
> the function at all.  The reason why we don't mark it as needed is  
> because
> the target back-end emits the constant address through its own  
> function
> and not through the normal way so we need to mark the SYMBOL_REF's  
> decl
> as being referenced.
>
> OK?

This mirrors what is done on rs6000 as well, previously you did:

r82141 | zack | 2004-05-22 11:18:46 -0700 (Sat, 22 May 2004) | 6 lines

2004-05-22  Andrew Pinski  <pinskia@physics.uc.edu>

        PR 15546
        * config/i386/i386.c (output_pic_addr_const <case SYMBOL_REF>):
        Call mark_decl_referenced on the SYMBOL_REF_DECL.

So, certainly the issue comes up from time to time,  :-(

but the mitigating factor appears to be:

r97287 | hubicka | 2005-03-30 14:28:02 -0800 (Wed, 30 Mar 2005) | 41  
lines

2005-03-31  Jan Hubicka  <jh@suse.cz>

        2004-11-02  Jan Hubicka  <jh@suse.cz>

        * cgraph.c (cgraph_varpool_node_name): New function.
        (dump_cgraph_varpool_node): New function.
        (dump_varpool): New function.
        * cgraphunit.c (cgraph_optimize): Dump varpool.

        2004-10-16  Jan Hubicka  <jh@suse.cz>

        * cgraph.c (decide_is_variable_needed): New function.
        (cgraph_varpool_finalize_decl): Use it.
        * cgraphunit.c (cgraph_optimize): Assemble_pending_decls  
when not doing
        unit-at-a-time.
        * final.c (output_addr_const): Do not call mark_referenced.
        * passes.c (rest_of_decl_compilation): ifdef out  
DECL_RTL_SET_P hack;
        always go via cgraph.
        * toplev.c (wrapup_global_declarations): Kill non-unit-at-a- 
time code.
        (check_global_declarations): Ifdef out code clearing DECL_RTL.
        * tree-optimize.c (execute_inline): Mark functions called.
        * i386.c (output_pic_addr_const): Do not call  
mark_decl_referenced.

        2004-10-11  Jan Hubicka  <jh@suse.cz>

        * cgraph.c (cgraph_varpool_first_unanalyzed_node): New  
global voriable
        (cgraph_varpool_last_needed_node): New static variable.
        (enqueue_needed_varpool_node): Break out from ...; add items  
to the
        end of queue; update first pointers.
        (cgraph_varpool_mark_needed_node): ... here.
        (cgraph_varpool_finalize_decl): Use  
enqueue_needed_varpool_node.
        (cgraph_varpool_assemble_pending_decls): Move to cgraphunit.c
        * cgraph.h (cgraph_varpool_node): Add analyzed field.
        (cgraph_varpool_first_unanalyzed_node): Declare.
        * cgraphunit.c: Include output.h.
        (cgraph_varpool_analyze_pending_decls): New function.
        (cgraph_varpool_assemble_pending_decls): Move from cgraph.c;  
bail out
        for errors, analyze pending decls.
        (cgraph_finalize_compilation_unit): Only analyze decls.
        (cgraph_optimize): Assemble the decls after expanding.

Oops.  Hopefully that can provide a hint of how `fix' this issue, or  
Jan can chime in and explain how to address this issue.  I'll leave  
this issue to rth and/or Jan to comment on.