[binutils-gdb] GC: Also check the local debug definition section

[H.J.Lu <hjl at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=9e223787a474c672c5f1cfd4574857241ae4eafa

commit 9e223787a474c672c5f1cfd4574857241ae4eafa
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Wed Mar 14 04:23:24 2018 -0700

    GC: Also check the local debug definition section
    
    Extend
    
    commit b7c871edcd83ccdc5fcd8148a7f433efd6b52255
    Author: H.J. Lu <hjl.tools@gmail.com>
    Date:   Wed May 17 07:57:15 2017 -0700
    
        Mark debug sections referenced by kept debug sections
    
    to handle the local debug definition section.
    
    bfd/
    
    	PR ld/20882
    	* elflink.c (elf_gc_mark_debug_section): Also check the local
    	debug definition section.
    
    ld/
    
    	PR ld/20882
    	* testsuite/ld-gc/pr20882.d: Also dump and check .debug_abbrev
    	section.
    	* testsuite/ld-gc/pr20882b.s: Add .debug_abbrev section.

Diff:
---
 bfd/ChangeLog                 |  6 ++++++
 bfd/elflink.c                 | 25 ++++++++++++++++++-------
 ld/ChangeLog                  |  7 +++++++
 ld/testsuite/ld-gc/pr20882.d  |  9 ++++++---
 ld/testsuite/ld-gc/pr20882b.s |  9 ++++++++-
 5 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index ddf0d04..ad971fc 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-14  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/20882
+	* elflink.c (elf_gc_mark_debug_section): Also check the local
+	debug definition section.
+
 2018-03-13  Nick Clifton  <nickc@redhat.com>
 
 	PR 22113
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 092edae..6a3d516 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -12802,20 +12802,31 @@ _bfd_elf_gc_mark_hook (asection *sec,
   return NULL;
 }
 
-/* Return the global debug definition section.  */
+/* Return the debug definition section.  */
 
 static asection *
 elf_gc_mark_debug_section (asection *sec ATTRIBUTE_UNUSED,
 			   struct bfd_link_info *info ATTRIBUTE_UNUSED,
 			   Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
 			   struct elf_link_hash_entry *h,
-			   Elf_Internal_Sym *sym ATTRIBUTE_UNUSED)
+			   Elf_Internal_Sym *sym)
 {
-  if (h != NULL
-      && (h->root.type == bfd_link_hash_defined
-	  || h->root.type == bfd_link_hash_defweak)
-      && (h->root.u.def.section->flags & SEC_DEBUGGING) != 0)
-    return h->root.u.def.section;
+  if (h != NULL)
+    {
+      /* Return the global debug definition section.  */
+      if ((h->root.type == bfd_link_hash_defined
+	   || h->root.type == bfd_link_hash_defweak)
+	  && (h->root.u.def.section->flags & SEC_DEBUGGING) != 0)
+	return h->root.u.def.section;
+    }
+  else
+    {
+      /* Return the local debug definition section.  */
+      asection *isec = bfd_section_from_elf_index (sec->owner,
+						   sym->st_shndx);
+      if ((isec->flags & SEC_DEBUGGING) != 0)
+	return isec;
+    }
 
   return NULL;
 }
diff --git a/ld/ChangeLog b/ld/ChangeLog
index a750599..e74f722 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,5 +1,12 @@
 2018-03-14  H.J. Lu  <hongjiu.lu@intel.com>
 
+	PR ld/20882
+	* testsuite/ld-gc/pr20882.d: Also dump and check .debug_abbrev
+	section.
+	* testsuite/ld-gc/pr20882b.s: Add .debug_abbrev section.
+
+2018-03-14  H.J. Lu  <hongjiu.lu@intel.com>
+
 	* testsuite/ld-gc/gc.exp: Fix a typo: $LFLAGS -> $LDFLAGS.
 
 2018-03-13  Nick Clifton  <nickc@redhat.com>
diff --git a/ld/testsuite/ld-gc/pr20882.d b/ld/testsuite/ld-gc/pr20882.d
index dd388c5..1d68d05 100644
--- a/ld/testsuite/ld-gc/pr20882.d
+++ b/ld/testsuite/ld-gc/pr20882.d
@@ -3,7 +3,10 @@
 #source: pr20882b.s
 #source: pr20882c.s
 #ld: --gc-sections -e main
-#readelf: -x .debug_info
+#readelf: -x .debug_info -x .debug_abbrev
 
-#...
-  0x0+ (0a000000 00000000 |00000000 0000000a |06000000 |00000006 |0400|0004)28 .*
+Hex dump of section '\.debug_info':
+  0x0+ .*
+
+Hex dump of section '\.debug_abbrev':
+  0x0+ 61626364 +abcd
diff --git a/ld/testsuite/ld-gc/pr20882b.s b/ld/testsuite/ld-gc/pr20882b.s
index ea0cf2e..baabf55 100644
--- a/ld/testsuite/ld-gc/pr20882b.s
+++ b/ld/testsuite/ld-gc/pr20882b.s
@@ -2,4 +2,11 @@
 	.hidden t.c.4903c230
 	.globl t.c.4903c230
 t.c.4903c230:
-	.byte 0x28
+	.dc.a  .Ldebug_abbrev0
+
+	.section .debug_abbrev,"",%progbits
+.Ldebug_abbrev0:
+	.byte 0x61
+	.byte 0x62
+	.byte 0x63
+	.byte 0x64