sh4-linux segfaults running ld testsuite

[Alan Modra]

Segmentation fault
FAIL: pr22269-1 (static pie undefined weak)
and others running "visibility (hidden undef)" tests

No code has any right to access bfd_link_hash_entry u.def without
first checking the type, and SYMBOL_REFERENCES_LOCAL isn't sufficient.

	* elf32-sh.c (sh_elf_finish_dynamic_symbol): Don't use relative
	relocs in GOT unless symbol is defined.

diff --git a/bfd/elf32-sh.c b/bfd/elf32-sh.c
index fdcc5870890..499233d1355 100644
--- a/bfd/elf32-sh.c
+++ b/bfd/elf32-sh.c
@@ -6174,6 +6174,8 @@ sh_elf_finish_dynamic_symbol (bfd *output_bfd, struct bfd_link_info *info,
 	 The entry in the global offset table will already have been
 	 initialized in the relocate_section function.  */
       if (bfd_link_pic (info)
+	  && (h->root.type == bfd_link_hash_defined
+	      || h->root.type == bfd_link_hash_defweak)
 	  && SYMBOL_REFERENCES_LOCAL (info, h))
 	{
 	  if (htab->fdpic_p)

-- 
Alan Modra
Australia Development Lab, IBM