binutils: backport R_XTENSA_DIFF* relocation signedness fix

This fixes the following build errors:

  qlatincodec.o:(.debug_line+0xcd7): dangerous relocation: overflow after relaxation
  qmetaobject.o:(.debug_frame+0xa89): dangerous relocation: overflow after relaxation

Fixes:
  http://autobuild.buildroot.net/results/f51/f51c87ae3c883cc36b06c0741999b52e48e4c943/
  http://autobuild.buildroot.net/results/bcb/bcbf25e4054911a7a192bdb5c92e0ebd50e9666c/
  http://autobuild.buildroot.net/results/8a8/8a8a0f8cca293ce1f383421ba8b1223b4266e3bc/
  http://autobuild.buildroot.net/results/a54/a54f3707781dc193292eda7d1723fce6487d6980/

Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/binutils/2.22/902-xtensa-gas-ld-diff-relocation-signed.patch

@@ -0,0 +1,133 @@
+From 6a17eba5358549d0d6d195bb22b34cdbc068def2 Mon Sep 17 00:00:00 2001
+From: Volodymyr Arbatov <arbatov@cadence.com>
+Date: Mon, 6 May 2013 09:43:21 -0800
+Subject: [PATCH] Use signed data type for R_XTENSA_DIFF* relocation offsets.
+
+R_XTENSA_DIFF relocation offsets are in fact signed. Treat them as such.
+Add testcase that examines ld behaviour on R_XTENSA_DIFF relocation
+changing sign during relaxation.
+
+2014-05-02  Volodymyr Arbatov  <arbatov@cadence.com>
+	    David Weatherford  <weath@cadence.com>
+	    Max Filippov  <jcmvbkbc@gmail.com>
+
+bfd/
+  * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as
+  signed.
+
+gas/
+  * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF*
+  fixups as signed.
+---
+Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6
+Changes to Changelog files and tests are dropped.
+
+ bfd/elf32-xtensa.c                       | 32 ++++++++++++-----------
+ gas/config/tc-xtensa.c                   |  3 +++
+ 2 files changed, 20 insertions(+), 15 deletions(-)
+
+diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c
+index edb04b4..8818d67 100644
+--- a/bfd/elf32-xtensa.c
++++ b/bfd/elf32-xtensa.c
+@@ -222,11 +222,11 @@ static reloc_howto_type elf_howto_table[] =
+ 	 FALSE, 0, 0, FALSE),
+ 
+   /* Relocations for supporting difference of symbols.  */
+-  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF8", FALSE, 0, 0xff, FALSE),
+-  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF16", FALSE, 0, 0xffff, FALSE),
+-  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF32", FALSE, 0, 0xffffffff, FALSE),
+ 
+   /* General immediate operand relocations.  */
+@@ -9013,7 +9013,8 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  || r_type == R_XTENSA_DIFF16
+ 		  || r_type == R_XTENSA_DIFF32)
+ 		{
+-		  bfd_vma diff_value = 0, new_end_offset, diff_mask = 0;
++		  bfd_signed_vma diff_value = 0;
++		  bfd_vma new_end_offset, diff_mask = 0;
+ 
+ 		  if (bfd_get_section_limit (abfd, sec) < old_source_offset)
+ 		    {
+@@ -9027,15 +9028,15 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+ 		      diff_value =
+-			bfd_get_8 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_8 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+ 		      diff_value =
+-			bfd_get_16 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_16 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+ 		      diff_value =
+-			bfd_get_32 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_32 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+@@ -9047,24 +9048,25 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  switch (r_type)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+-		      diff_mask = 0xff;
+-		      bfd_put_8 (abfd, diff_value,
++		      diff_mask = 0x7f;
++		      bfd_put_signed_8 (abfd, diff_value,
+ 				 &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+-		      diff_mask = 0xffff;
+-		      bfd_put_16 (abfd, diff_value,
++		      diff_mask = 0x7fff;
++		      bfd_put_signed_16 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+-		      diff_mask = 0xffffffff;
+-		      bfd_put_32 (abfd, diff_value,
++		      diff_mask = 0x7fffffff;
++		      bfd_put_signed_32 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+-		  /* Check for overflow.  */
+-		  if ((diff_value & ~diff_mask) != 0)
++		  /* Check for overflow. Sign bits must be all zeroes or all ones */
++		  if ((diff_value & ~diff_mask) != 0 &&
++		      (diff_value & ~diff_mask) != (-1 & ~diff_mask))
+ 		    {
+ 		      (*link_info->callbacks->reloc_dangerous)
+ 			(link_info, _("overflow after relaxation"),
+diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c
+index 58ace38..7547c0a0 100644
+--- a/gas/config/tc-xtensa.c
++++ b/gas/config/tc-xtensa.c
+@@ -5867,12 +5867,15 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg)
+ 	    {
+ 	    case BFD_RELOC_8:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_16:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_32:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    default:
+ 	      break;
+-- 
+1.8.1.4
+

package/binutils/2.23.1/902-xtensa-gas-ld-diff-relocation-signed.patch

@@ -0,0 +1,133 @@
+From 6a17eba5358549d0d6d195bb22b34cdbc068def2 Mon Sep 17 00:00:00 2001
+From: Volodymyr Arbatov <arbatov@cadence.com>
+Date: Mon, 6 May 2013 09:43:21 -0800
+Subject: [PATCH] Use signed data type for R_XTENSA_DIFF* relocation offsets.
+
+R_XTENSA_DIFF relocation offsets are in fact signed. Treat them as such.
+Add testcase that examines ld behaviour on R_XTENSA_DIFF relocation
+changing sign during relaxation.
+
+2014-05-02  Volodymyr Arbatov  <arbatov@cadence.com>
+	    David Weatherford  <weath@cadence.com>
+	    Max Filippov  <jcmvbkbc@gmail.com>
+
+bfd/
+  * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as
+  signed.
+
+gas/
+  * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF*
+  fixups as signed.
+---
+Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6
+Changes to Changelog files and tests are dropped.
+
+ bfd/elf32-xtensa.c                       | 32 ++++++++++++-----------
+ gas/config/tc-xtensa.c                   |  3 +++
+ 2 files changed, 20 insertions(+), 15 deletions(-)
+
+diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c
+index edb04b4..8818d67 100644
+--- a/bfd/elf32-xtensa.c
++++ b/bfd/elf32-xtensa.c
+@@ -222,11 +222,11 @@ static reloc_howto_type elf_howto_table[] =
+ 	 FALSE, 0, 0, FALSE),
+ 
+   /* Relocations for supporting difference of symbols.  */
+-  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF8", FALSE, 0, 0xff, FALSE),
+-  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF16", FALSE, 0, 0xffff, FALSE),
+-  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF32", FALSE, 0, 0xffffffff, FALSE),
+ 
+   /* General immediate operand relocations.  */
+@@ -9013,7 +9013,8 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  || r_type == R_XTENSA_DIFF16
+ 		  || r_type == R_XTENSA_DIFF32)
+ 		{
+-		  bfd_vma diff_value = 0, new_end_offset, diff_mask = 0;
++		  bfd_signed_vma diff_value = 0;
++		  bfd_vma new_end_offset, diff_mask = 0;
+ 
+ 		  if (bfd_get_section_limit (abfd, sec) < old_source_offset)
+ 		    {
+@@ -9027,15 +9028,15 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+ 		      diff_value =
+-			bfd_get_8 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_8 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+ 		      diff_value =
+-			bfd_get_16 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_16 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+ 		      diff_value =
+-			bfd_get_32 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_32 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+@@ -9047,24 +9048,25 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  switch (r_type)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+-		      diff_mask = 0xff;
+-		      bfd_put_8 (abfd, diff_value,
++		      diff_mask = 0x7f;
++		      bfd_put_signed_8 (abfd, diff_value,
+ 				 &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+-		      diff_mask = 0xffff;
+-		      bfd_put_16 (abfd, diff_value,
++		      diff_mask = 0x7fff;
++		      bfd_put_signed_16 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+-		      diff_mask = 0xffffffff;
+-		      bfd_put_32 (abfd, diff_value,
++		      diff_mask = 0x7fffffff;
++		      bfd_put_signed_32 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+-		  /* Check for overflow.  */
+-		  if ((diff_value & ~diff_mask) != 0)
++		  /* Check for overflow. Sign bits must be all zeroes or all ones */
++		  if ((diff_value & ~diff_mask) != 0 &&
++		      (diff_value & ~diff_mask) != (-1 & ~diff_mask))
+ 		    {
+ 		      (*link_info->callbacks->reloc_dangerous)
+ 			(link_info, _("overflow after relaxation"),
+diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c
+index 58ace38..7547c0a0 100644
+--- a/gas/config/tc-xtensa.c
++++ b/gas/config/tc-xtensa.c
+@@ -5867,12 +5867,15 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg)
+ 	    {
+ 	    case BFD_RELOC_8:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_16:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_32:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    default:
+ 	      break;
+-- 
+1.8.1.4
+

package/binutils/2.23.2/902-xtensa-gas-ld-diff-relocation-signed.patch

@@ -0,0 +1,133 @@
+From 6a17eba5358549d0d6d195bb22b34cdbc068def2 Mon Sep 17 00:00:00 2001
+From: Volodymyr Arbatov <arbatov@cadence.com>
+Date: Mon, 6 May 2013 09:43:21 -0800
+Subject: [PATCH] Use signed data type for R_XTENSA_DIFF* relocation offsets.
+
+R_XTENSA_DIFF relocation offsets are in fact signed. Treat them as such.
+Add testcase that examines ld behaviour on R_XTENSA_DIFF relocation
+changing sign during relaxation.
+
+2014-05-02  Volodymyr Arbatov  <arbatov@cadence.com>
+	    David Weatherford  <weath@cadence.com>
+	    Max Filippov  <jcmvbkbc@gmail.com>
+
+bfd/
+  * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as
+  signed.
+
+gas/
+  * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF*
+  fixups as signed.
+---
+Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6
+Changes to Changelog files and tests are dropped.
+
+ bfd/elf32-xtensa.c                       | 32 ++++++++++++-----------
+ gas/config/tc-xtensa.c                   |  3 +++
+ 2 files changed, 20 insertions(+), 15 deletions(-)
+
+diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c
+index edb04b4..8818d67 100644
+--- a/bfd/elf32-xtensa.c
++++ b/bfd/elf32-xtensa.c
+@@ -222,11 +222,11 @@ static reloc_howto_type elf_howto_table[] =
+ 	 FALSE, 0, 0, FALSE),
+ 
+   /* Relocations for supporting difference of symbols.  */
+-  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF8", FALSE, 0, 0xff, FALSE),
+-  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF16", FALSE, 0, 0xffff, FALSE),
+-  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF32", FALSE, 0, 0xffffffff, FALSE),
+ 
+   /* General immediate operand relocations.  */
+@@ -9013,7 +9013,8 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  || r_type == R_XTENSA_DIFF16
+ 		  || r_type == R_XTENSA_DIFF32)
+ 		{
+-		  bfd_vma diff_value = 0, new_end_offset, diff_mask = 0;
++		  bfd_signed_vma diff_value = 0;
++		  bfd_vma new_end_offset, diff_mask = 0;
+ 
+ 		  if (bfd_get_section_limit (abfd, sec) < old_source_offset)
+ 		    {
+@@ -9027,15 +9028,15 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+ 		      diff_value =
+-			bfd_get_8 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_8 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+ 		      diff_value =
+-			bfd_get_16 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_16 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+ 		      diff_value =
+-			bfd_get_32 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_32 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+@@ -9047,24 +9048,25 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  switch (r_type)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+-		      diff_mask = 0xff;
+-		      bfd_put_8 (abfd, diff_value,
++		      diff_mask = 0x7f;
++		      bfd_put_signed_8 (abfd, diff_value,
+ 				 &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+-		      diff_mask = 0xffff;
+-		      bfd_put_16 (abfd, diff_value,
++		      diff_mask = 0x7fff;
++		      bfd_put_signed_16 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+-		      diff_mask = 0xffffffff;
+-		      bfd_put_32 (abfd, diff_value,
++		      diff_mask = 0x7fffffff;
++		      bfd_put_signed_32 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+-		  /* Check for overflow.  */
+-		  if ((diff_value & ~diff_mask) != 0)
++		  /* Check for overflow. Sign bits must be all zeroes or all ones */
++		  if ((diff_value & ~diff_mask) != 0 &&
++		      (diff_value & ~diff_mask) != (-1 & ~diff_mask))
+ 		    {
+ 		      (*link_info->callbacks->reloc_dangerous)
+ 			(link_info, _("overflow after relaxation"),
+diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c
+index 58ace38..7547c0a0 100644
+--- a/gas/config/tc-xtensa.c
++++ b/gas/config/tc-xtensa.c
+@@ -5867,12 +5867,15 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg)
+ 	    {
+ 	    case BFD_RELOC_8:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_16:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_32:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    default:
+ 	      break;
+-- 
+1.8.1.4
+

package/binutils/2.24/902-xtensa-gas-ld-diff-relocation-signed.patch

@@ -0,0 +1,133 @@
+From 6a17eba5358549d0d6d195bb22b34cdbc068def2 Mon Sep 17 00:00:00 2001
+From: Volodymyr Arbatov <arbatov@cadence.com>
+Date: Mon, 6 May 2013 09:43:21 -0800
+Subject: [PATCH] Use signed data type for R_XTENSA_DIFF* relocation offsets.
+
+R_XTENSA_DIFF relocation offsets are in fact signed. Treat them as such.
+Add testcase that examines ld behaviour on R_XTENSA_DIFF relocation
+changing sign during relaxation.
+
+2014-05-02  Volodymyr Arbatov  <arbatov@cadence.com>
+	    David Weatherford  <weath@cadence.com>
+	    Max Filippov  <jcmvbkbc@gmail.com>
+
+bfd/
+  * elf32-xtensa.c (relax_section): treat R_XTENSA_DIFF* relocations as
+  signed.
+
+gas/
+  * config/tc-xtensa.c (md_apply_fix): mark BFD_RELOC_XTENSA_DIFF*
+  fixups as signed.
+---
+Backported from: 1058c7532d0b012ac329219264ddad59049fb6e6
+Changes to Changelog files and tests are dropped.
+
+ bfd/elf32-xtensa.c                       | 32 ++++++++++++-----------
+ gas/config/tc-xtensa.c                   |  3 +++
+ 2 files changed, 20 insertions(+), 15 deletions(-)
+
+diff --git a/bfd/elf32-xtensa.c b/bfd/elf32-xtensa.c
+index edb04b4..8818d67 100644
+--- a/bfd/elf32-xtensa.c
++++ b/bfd/elf32-xtensa.c
+@@ -222,11 +222,11 @@ static reloc_howto_type elf_howto_table[] =
+ 	 FALSE, 0, 0, FALSE),
+ 
+   /* Relocations for supporting difference of symbols.  */
+-  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF8", FALSE, 0, 0xff, FALSE),
+-  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF16, 0, 1, 16, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF16", FALSE, 0, 0xffff, FALSE),
+-  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
++  HOWTO (R_XTENSA_DIFF32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
+ 	 bfd_elf_xtensa_reloc, "R_XTENSA_DIFF32", FALSE, 0, 0xffffffff, FALSE),
+ 
+   /* General immediate operand relocations.  */
+@@ -9013,7 +9013,8 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  || r_type == R_XTENSA_DIFF16
+ 		  || r_type == R_XTENSA_DIFF32)
+ 		{
+-		  bfd_vma diff_value = 0, new_end_offset, diff_mask = 0;
++		  bfd_signed_vma diff_value = 0;
++		  bfd_vma new_end_offset, diff_mask = 0;
+ 
+ 		  if (bfd_get_section_limit (abfd, sec) < old_source_offset)
+ 		    {
+@@ -9027,15 +9028,15 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+ 		      diff_value =
+-			bfd_get_8 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_8 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+ 		      diff_value =
+-			bfd_get_16 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_16 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+ 		      diff_value =
+-			bfd_get_32 (abfd, &contents[old_source_offset]);
++			bfd_get_signed_32 (abfd, &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+@@ -9047,24 +9048,25 @@ relax_section (bfd *abfd, asection *sec, struct bfd_link_info *link_info)
+ 		  switch (r_type)
+ 		    {
+ 		    case R_XTENSA_DIFF8:
+-		      diff_mask = 0xff;
+-		      bfd_put_8 (abfd, diff_value,
++		      diff_mask = 0x7f;
++		      bfd_put_signed_8 (abfd, diff_value,
+ 				 &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF16:
+-		      diff_mask = 0xffff;
+-		      bfd_put_16 (abfd, diff_value,
++		      diff_mask = 0x7fff;
++		      bfd_put_signed_16 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    case R_XTENSA_DIFF32:
+-		      diff_mask = 0xffffffff;
+-		      bfd_put_32 (abfd, diff_value,
++		      diff_mask = 0x7fffffff;
++		      bfd_put_signed_32 (abfd, diff_value,
+ 				  &contents[old_source_offset]);
+ 		      break;
+ 		    }
+ 
+-		  /* Check for overflow.  */
+-		  if ((diff_value & ~diff_mask) != 0)
++		  /* Check for overflow. Sign bits must be all zeroes or all ones */
++		  if ((diff_value & ~diff_mask) != 0 &&
++		      (diff_value & ~diff_mask) != (-1 & ~diff_mask))
+ 		    {
+ 		      (*link_info->callbacks->reloc_dangerous)
+ 			(link_info, _("overflow after relaxation"),
+diff --git a/gas/config/tc-xtensa.c b/gas/config/tc-xtensa.c
+index 58ace38..7547c0a0 100644
+--- a/gas/config/tc-xtensa.c
++++ b/gas/config/tc-xtensa.c
+@@ -5867,12 +5867,15 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg)
+ 	    {
+ 	    case BFD_RELOC_8:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF8;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_16:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF16;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    case BFD_RELOC_32:
+ 	      fixP->fx_r_type = BFD_RELOC_XTENSA_DIFF32;
++	      fixP->fx_signed = 1;
+ 	      break;
+ 	    default:
+ 	      break;
+-- 
+1.8.1.4
+