Re: Linking very large programs with inadequate branch displacements

[Bill Yoder <byoder at cs dot utexas dot edu>]

Hi, All:

> > Alan, I can't figure out how to hit a breakpoint at
> > ppc_elf_relax_section:elf32-ppc.c.  Is there a command line switch I
> > should throw,
>
> Pass --relax to ld.

I have written a trips_elf_relax_section() that appends trampolines  
to the end of each .text section that needs them.  Well and good.   
The problem is, I cannot get the front end to expand the text  
sections to accommodate the new trampolines.

The steps include:
* bfd_realloc() the contents with a space large enough for the  
appended trampolines.
* Update sec->_raw_size with the new section size.
* Update elf_section_data (sec)->this_hdr.contents with the new  
contents.
* Set *again to 'true' before returning to lang_size_sections_1().

Despite these steps, the front end calls the  
trips_elf_relocate_section() with no adjustment to the original  
section sizes.  What is the key to true relaxation?  Does it matter  
that I'm working with 2.12.90 sources?

Thanks in advance,
Bill