[PATCH] RISC-V: Fix a gp relaxation reloc overflow error.

[Jim Wilson <jimw at sifive dot com>]

This was broken when I changed how we compute the value for the gp register.
It used to be computed inside the sdata section.  Now it is computed at the
end which makes it an abs section symbol.  There is code that tries to use
the alignment of the section that the gp value is in, but this does not work
if it is in the abs section, as the abs section has alignment of 1 byte.
There are people using alternative linker scripts that still define it in the
sdata section, so the code is still useful.  Thus adding a check to disable
this when gp is in the abs section.

This was tested with 32/64 elf/linux cross binutils build and check.  There
were no regressions.  It was also tested with the original testcase, and fixes
the relocation overflow error for that testcase.

Committed.

Jim

	bfd/
	* elfnn-riscv.c (_bfd_riscv_relax_lui): Add check to exclude abs
	section when setting max_alignment.  Update comment.
	(_bfd_riscv_relax_pc): Likewise.
---
 bfd/elfnn-riscv.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
index d14c29e833..4729bae09a 100644
--- a/bfd/elfnn-riscv.c
+++ b/bfd/elfnn-riscv.c
@@ -3533,12 +3533,13 @@ _bfd_riscv_relax_lui (bfd *abfd,
 
   if (gp)
     {
-      /* If gp and the symbol are in the same output section, then
-	 consider only that section's alignment.  */
+      /* If gp and the symbol are in the same output section, which is not the
+	 abs section, then consider only that output section's alignment.  */
       struct bfd_link_hash_entry *h =
 	bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, FALSE, FALSE,
 			      TRUE);
-      if (h->u.def.section->output_section == sym_sec->output_section)
+      if (h->u.def.section->output_section == sym_sec->output_section
+	  && sym_sec->output_section != bfd_abs_section_ptr)
 	max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
     }
 
@@ -3767,11 +3768,13 @@ _bfd_riscv_relax_pc  (bfd *abfd ATTRIBUTE_UNUSED,
 
   if (gp)
     {
-      /* If gp and the symbol are in the same output section, then
-	 consider only that section's alignment.  */
+      /* If gp and the symbol are in the same output section, which is not the
+	 abs section, then consider only that output section's alignment.  */
       struct bfd_link_hash_entry *h =
-	bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, FALSE, FALSE, TRUE);
-      if (h->u.def.section->output_section == sym_sec->output_section)
+	bfd_link_hash_lookup (link_info->hash, RISCV_GP_SYMBOL, FALSE, FALSE,
+			      TRUE);
+      if (h->u.def.section->output_section == sym_sec->output_section
+	  && sym_sec->output_section != bfd_abs_section_ptr)
 	max_alignment = (bfd_vma) 1 << sym_sec->output_section->alignment_power;
     }
 
-- 
2.17.1