relaxing vs section merging

[DJ Delorie]

target = mn10300-elf
host = linux

Consider linking these two files with "ld --relax":

-------------------- dj1.s
	.section .text
	.global _start
	.type	_start,@function
_start:
	mov	.LC1a,d1
	nop

	.section	.rodata.str1.1,"aMS",@progbits,1
.LC1a:
	.string	"\n"
-------------------- dj2.s
	.section	.rodata.str1.1,"aMS",@progbits,1
.LC2a:
	.rept	32768
	.byte	'a'
	.endr
	.byte	0
.LC2b:
	.string	"abc\n"
--------------------

What I'm seeing is that the relaxation code uses the pre-merge value
of LC1a, but the relocation uses the post-merge value and thus fails
(reloc overflow).  I've verified that merging happens before relaxing.

Why this happens is uncertain.  Various things I've seen:

* The section for LC1a is set to *ABS* by ldlang.c, because the merge
  code decided it was to be discarded.

* If I try to map LC1a through _bfd_elf_rela_local_sym, at first it
  doesn't because only STT_SECTION symbols are allowed to be mapped.

* If I override the STT_SECTION check, it complains that the symbol is
  outside the merged section (*ABS*, remember?)

* If I try to keep the section from being discarded (so it's not
  *ABS*), it still complains as above.

So far, the only "solution" I've found is to just not relax relocs to
symbols in mergable sections, but this obviously isn't ideal.  Am I
missing something obvious?  Is there some fundamental bug that needs
to be fix here, and if so, where?  Or should we just skip mergable
symbols?